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Prothallus Stock Photos and Images
RFJ57PDJ–Microscopic view of fern prothallium (prothallus) with removed chlorophyll. Rheinberg illumination.
RFT60MBA–A cross sectional picture of Fern prothallus showing antheridia, sperms and rhizoids, vintage line drawing or engraving illustration.
RFT5N7G7–This is a structure of Young ProThallus of Fern. It has following organs proThallus, root-hairs, antheridia, archegonia, vintage line drawing or engra
RF2A5NP83–Leafy Xanthoria lichen, named from the Greek 'xanthos' meaning yellow. A Nitrogen loving lichen, indicates presence of Nitrogen pollutants.
RM2AN7Y95–Lectures on the physiology of plants . Fig. 425.-^4 male prothallus of Equisctuntarvense, with the first antheridia a (after Hof-meister, X 200). B—F- antlierozoids of EquisctumTeimateia (after Schacht)..
RMPFM4FF–. Cyclopedia of American horticulture, comprising suggestions for cultivation of horticultural plants, descriptions of the species of fruits, vegetables, flowers, and ornamental plants sold in the United States and Canada, together with geographical and biographical sketches. Gardening. 576 FERN FERN is impure and full of the spores of low forms of plant life, which are very destructive to the prothalli of Ferns. To prevent this, the workshop should be pro- vided with a receptacle in which the water intended for use on Ferns while in the prothallus state can be raised to a boiling temperature,
RMMA76R2–. Elementary biology; an introduction to the science of life . 5 ( X 80) « ( X 10) Fig. 150. Reproduction in fern X 300) The gamete-bearing plant, <?, of the fern, called a./'j-othallus, is a flat plate of cells, with hairlike roots on the undersUr- face. Flask-shaped organs, b, each bearing a single egg cell, are embedded on the undersurface, near the notch, with the mouth pointing downward and backward. Near the small end of the prothallus, on the undersurface, are the organs, c, bearing the male gametes. These are dis- charged into the water, and swim about freely, finding their way into
RFT5X53H–A picture of Young ProThallus of Fern. It consists of a primary root, primary leaf, the rudiment of a new stem, and an organ, vintage line drawing or
RF2A5NPA9–Leafy Xanthoria lichen, named from the Greek 'xanthos' meaning yellow. A Nitrogen loving lichen, indicates presence of Nitrogen pollutants.
RM2ANDP6C–Organography of plants, especially of the archegoniatae and spermaphyta . h antheridia andarchegonia occur together upon theprothallus^ and as in most Pteridophytathe antheridia appear earlier (Figs. 140,Aii 141, ^) than the archegonia, and asregards their point of origin are lessrestricted than the archegonia, beingfound both upon the lobes and uponthe body of the prothallus. The arche-gonia are confined to the meristemimmediately under the crown of lobes.The prothallus of Lycopodiumsalakense is similarly chlorophyllous,but has no crown of lobes or only anindication of these, and perhaps thi
RFT5YMD1–This is image of Germination fern of organ which is a: Before germination; b: early stage and showing protonema; c, d, e & f: successive stages in the
RMPFN3RM–. Cyclopedia of American horticulture, comprising suggestions for cultivation of horticultural plants, descriptions of the species of fruits, vegetables, flowers, and ornamental plants sold in the United States and Canada, together with geographical and biographical sketches. Gardening. 576 FERN is impure and full of the spores of low forms of plant life, which are very (lestruetive to the prothalli of Ferns. To prevent this, the workshop should be pro- vided with a receptacle in which the water intended for use on Ferns while in the prothallus state can be raised to a boiling temperature, whi
RF2A538KB–Leafy Xanthoria lichen growing on the bark of an Ash,from the Greek 'xanthos' meaning yellow. Nitrogen loving lichen, indicates Nitrogen pollutants.
RM2ANDNWM–Organography of plants, especially of the archegoniatae and spermaphyta . n Vorkeimes bei den heterosporen Lycopodiaceen,in Botanische Zeitung, liv (1896), p. 159. * Buchtien, Entwicklungsgeschichte des Prothallium von Equisetum, in Bibliotheca Botanica,viii (18S7). In most homosporous Pteridophyta the prothallus produces first of all antheridia. It is probablethat in Equisetum it would be possible by feeding to cause the male prothallus to develop into theiemale. It is, however, scarcely to be expected even if one sowed the spores singly in apparentlyquite similar conditions that they would a
RMPG2KC2–. Pharmaceutical botany. Botany; Botany, Medical. 68 PHARMACEUTICAL BOTANY moving through the water are drawn by a chemotactic influence to the archegonia of another prothallus, pass down the neck canals of these and fuse with the ova, fertilizing them. The fertilized egg or. Fig. 37.—Dryopteris filix-mas—Plant and section through sorus. {From Sayre.) oospore divides and redivides and soon becomes differentiated into stem bud, first leaf, root, and foot. The foot obtains nourishment from the prothallus until the root grows into the soil, when it atrophies and the sporophyte becomes independent
RMRWPP69–The elements of botany for The elements of botany for beginners and for schools elementsbotany00gray Year: 1887 Fig. 509. A young prothallus of a Maiden-hair, moderately enlarged, and an older one with the first fern-leaf developed from near the notch. 510. Middle por- tion of the young one, nmcli magnified, sliowinic below, partly among tlie rootlets, the nntheridia or fertilizing organs, and above, near the notch, tliiee pistillidia to be fertilized.
RF2A5NP4A–Leafy Xanthoria lichen, named from the Greek 'xanthos' meaning yellow. A Nitrogen loving lichen, indicates presence of Nitrogen pollutants.
RM2AG1FD0–. The theory of evolution in the light of facts. here still remain three cells, which may be regardedas a prothallus (the so-called three antipodes). Thereis never more than one ovum formed (Fig. 29). The determination of classeswithin these series is effectedmostly according to the construc-tion and the position of the spores—or the ovum and seed vessels,the formation and arrangement ofthe leaves, the small or tree-hkeconstitution of the stem (stalk),etc. From all this there results ahabit of growth which is fairlycharacteristic but can only be suf-ficiently known by seeing theplants. As an e
RMPG2RKN–. Heredity and evolution in plants. Heredity; Plants. LIFE HISTORY OF A FEEN 23 16. Fertilization.—Neither the eggs nor the sperms are able, independently, to reproduce their kind. In order to accomplish this they must unite, and the fusion of the sperm and egg is fertiHzation. One of the most significant facts about fertilization in ferns is that free water is re- quired, in order that the sperms may reach the egg by their own locomotion. When the antheridia and archegonia. Fig. 23.—Fern prothallus; cross-sections showing antheridia {an), sperms {sp), and rhizoids {rh). Below at the right is
RMT0CXFD–Elementary biology; an introduction to Elementary biology; an introduction to the science of life elementarybiolog00grue Year: 1924 ALTERNATION OF GENERATIONS 323 than the nail of your little finger, called a prothallus (see Fig. 15 o). Prothalli are often found growing on flowerpots in greenhouses. The prothallus corresponds to the gametophyte of the moss, while the plant which is familiar to us as the fern is a sporophyte. The Fig. 151. Alternation of generations in the life history of the fern G. the gametophyte, or gamete-bearing plant; /, the female gamete organ ; m, the male gamete o
RF2A538X3–Leafy Xanthoria lichen growing on the bark of an Ash,from the Greek 'xanthos' meaning yellow. Nitrogen loving lichen, indicates Nitrogen pollutants.
RM2ANDK7N–Organography of plants, especially of the archegoniatae and spermaphyta . ^^s-^ w h Fig. 144. Hemitelia (Amphicosmia) Walkerae. Development of pro-thallus. I, young prothallus ; w/t, rhizoid. 2 and 3, older prothalli, eachwith two vegetative points, f, v. Magnified ; 1 more highly so than 2 and 3. HEART-SHAPED PROTHALLI OF POLYPODIACEAE 201 much as such epiphytic prothalli evidently can only develop archegoniain special favourable conditions, and they live vegetatively between times ;.
![. Studies in fossil botany . Paleobotany. 196 STUDIES IN FOSSIL BOTANY name Cardiocarpon anomalum of Williamson* (not of Carruthers). The seeds, which attained a great size, became detached, together with the remains of the sporophyll, and in this condition were never suspected of belonging to a Lycopod until their origin had been traced. The prothallus within the megaspore is not un- commonly preserved (see Figs. 81, 82), and is found in the younger stage, before the integument has grown up, as well as in the mature ''seeds." The tissue of the prothallus may show a considerable amount of Stock Photo](https://c8.alamy.com/comp/PG172T/studies-in-fossil-botany-paleobotany-196-studies-in-fossil-botany-name-cardiocarpon-anomalum-of-williamson-not-of-carruthers-the-seeds-which-attained-a-great-size-became-detached-together-with-the-remains-of-the-sporophyll-and-in-this-condition-were-never-suspected-of-belonging-to-a-lycopod-until-their-origin-had-been-traced-the-prothallus-within-the-megaspore-is-not-un-commonly-preserved-see-figs-81-82-and-is-found-in-the-younger-stage-before-the-integument-has-grown-up-as-well-as-in-the-mature-seedsquot-the-tissue-of-the-prothallus-may-show-a-considerable-amount-of-PG172T.jpg ". Studies in fossil botany . Paleobotany. 196 STUDIES IN FOSSIL BOTANY name Cardiocarpon anomalum of Williamson* (not of Carruthers). The seeds, which attained a great size, became detached, together with the remains of the sporophyll, and in this condition were never suspected of belonging to a Lycopod until their origin had been traced. The prothallus within the megaspore is not un- commonly preserved (see Figs. 81, 82), and is found in the younger stage, before the integument has grown up, as well as in the mature ''seeds." The tissue of the prothallus may show a considerable amount of Stock Photo")
RMPG172T–. Studies in fossil botany . Paleobotany. 196 STUDIES IN FOSSIL BOTANY name Cardiocarpon anomalum of Williamson* (not of Carruthers). The seeds, which attained a great size, became detached, together with the remains of the sporophyll, and in this condition were never suspected of belonging to a Lycopod until their origin had been traced. The prothallus within the megaspore is not un- commonly preserved (see Figs. 81, 82), and is found in the younger stage, before the integument has grown up, as well as in the mature ''seeds." The tissue of the prothallus may show a considerable amount of
RMRWK5D8–The elements of botany for The elements of botany for beginners and for schools elementsbotany00gray Year: 1887 160 CRYPTOGAMOUS OR FLOWERLESS PLANTS. [SECTION 17. closely resembles a small Liverwort. This is named a Prothallus (Fig. 509): from some point of this a bud appears to originate, which produces the first fern-leaf, soon followed by a second and third, and so the stem and leaves of the plant are set up. 490. Investigation of tliis prothallus under the microscope resulted in the discovery of a wholly unsuspected kind of fertilization, takin? place at this germinating stage of the
RF2A5393N–Leafy Xanthoria lichen growing on the bark of an Ash,from the Greek 'xanthos' meaning yellow. Nitrogen loving lichen, indicates Nitrogen pollutants.
RM2ANDGXJ–Organography of plants, especially of the archegoniatae and spermaphyta . eing better fed, where broad wings have developed,beneath which drops of water (in-dicated by dots) collect. very poor in nutriment. Prothalli of Polypodiaceae wanting the Heart-like Outline. Anogramme. The prothallus of the genus Anogramme connects withthe forms in which the formation of the two wings takes place at different How they arise we shall not stop to inquire. 2o6 CONFIGURATION OF THE PROTHALLUS OF PTERIDOPHYTA times. On account of its noteworthy adaptations it will be mentionedparticularly below ^. It produce
RMPG1DFE–. Heredity in relation to evolution and animal breeding, . Heredity. HEEEDITY all other cells of the prothallus are already in tlie reduced condition without any matura- tion divisions. The result of their union in pairs, at fertilization, is the formation of 2 N combinations that germinate into fern-plants. Similarly in the case of a male animal which. Fig. 8. — Diagram showing the chromosome number in the spermatogenesis of ordinary animals (upper Une) and of the wasp (lower line). has developed from a reduced but unfertilized egg, no reduction occurs at the formation of its sperm-cells. In
RMRWK5D5–The elements of botany for The elements of botany for beginners and for schools elementsofbotany00gray Year: 1887 160 CRYPTOGAMOUS OR FLOWERLESS PLANTS. [SECTION 17. closely resembles a small Liverwort. This is named a Prothallus (Fig. 509): from some point of this a bud appears to originate, which produces the first fern-leaf, soon followed by a second and third, and so the stem and leaves of the plant are set up. 490. Investigation of this prothallus under the microscope resulted in the discovery of a wholly unsuspected kind of fertilization, taking place at this germinating stage of the
RF2A53997–Leafy Xanthoria lichen growing on the bark of an Ash,from the Greek 'xanthos' meaning yellow. Nitrogen loving lichen, indicates Nitrogen pollutants.
RM2ANDCMJ–Organography of plants, especially of the archegoniatae and spermaphyta . rmationof sclerotia occurs in different cycles of affinity in the Hepaticie. See p. 66. 2i6 PHENOMENA OF ADAPTATION OF THE PROTHALLUS Anogramme belongs to that group of Filicineae in which the prothalluswith heart-like outline does not appear, and indeed we might regard theprothallus of Anogramme chaerophylla^, as it is shown in Fig. 158, as quitethat of Gymnogramme or of Pteris longifolia, on which the second winghad not yet been developed, and the meristem was lateral. Old prothalliare funnel-shaped, not flattened as i
RMPG15R9–. Fossil plants : for students of botany and geology . Paleobotany. Fig. 783. PUyostrohus (Pinites) macrocephalus. (After Gardner; nat. size.) i^2!^ ^ w-^^^^ ^^hL ''' pf^^ 1 ^ 1. Fig. 784. Piiyostrobus (Pinilea) macrocephalus. A, section of an ovule; n, nucellus. B, longitudinal section of part of the cone. (From sections in the British Museum; B, slightly reduced.) prothallus tent-pole of Ginkgo ovules: at its blunt apex are two winged pollen-grains. Prothallus-tissue is also represented. Carriithers compared the species with Pinus Pinaster but the. Please note that these images are extracte
RF2A5NPC7–Leafy Xanthoria lichen, named from the Greek 'xanthos' meaning yellow. A Nitrogen loving lichen, indicates presence of Nitrogen pollutants.
RM2ANDFN5–Organography of plants, especially of the archegoniatae and spermaphyta . ether adaptation can be proved in the other peculiar features of theprothallus. See p. 25. ^ See p. 180. FEMALE PROTHALLUS OF SALVINIACEAE •211 SALVINIACEAE. The female prothallus of Salviniaceae resembles thatof Marsiliaceae in so far as it is only formed at the apex of the megaspore(Fig. 156) ; the greater portion of the internal space of the megasporeremains as a reservoir of reser^e-material. The prothallus is chlorophyllousand in varying degree, that of Salvinia has much, that of Azolla carolinianavery little chlor
RMPG2RM2–. Heredity and evolution in plants. Heredity; Plants. Fig. ig.—Germination of the spores of a fern, a, Before germination; b, early stage, showing protonema (pr.), and first rhizoid (rh); c, d, e, f, successive stages in the development of the prothallus.. Fig. 20.—Prothallus of a fern. Archegonia on the (central) cushion near the notch; antheridia among the rhizoids, below. (After Margaret C. Ferguson.). Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly
RF2A53BHF–Pale grey lichen ( Lecanora campestris subsp. campestris ) on a horizontal gravestone. Lecanoraceae
RM2AN7TM7–Lectures on the physiology of plants . bryo; w its root;s its stem-apex ; * its first leaf, which distendsthe prothallus ; si gelatinous envelope of thespore ; at first it forms the funnel above thepapilla, and it still envelopes the prothallium(50 hours after sowing). contam numerous microspores. EMBRYOLOGV OF SELAGINELLAE, ETC. 749 oosphere; the suppression of the fertilisation and development of the embryo whenthe access of antherozoids is prevented, however, is a certain proof of the necessityof the union for the formation of an embryo. The processes of reproduction which alone interest us
RMPG2RM9–. Heredity and evolution in plants. Heredity; Plants. i8 HEREDITY AND EVOLUTION IN PLANTS. Fig. ig.—Germination of the spores of a fern, a, Before germination; b, early stage, showing protonema (pr.), and first rhizoid (rh); c, d, e, f, successive stages in the development of the prothallus.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Gager, C. Stuart (Charles Stuart), 1872-1943. Philadelphia, P. Blakiston's Son &
RF2A53BTP–Pale grey lichen ( Lecanora campestris subsp. campestris ) on a horizontal gravestone. Lecanoraceae
RM2AXD6J0–Plants and their ways in South Africa . of the spore. These eachdivide twice, forming four nucleiat each end. Of these, three atthe micropylar end form the eggapparatus, the largest of the threebecoming the egg. Of the fourat the opposite end, three surroundthemselves with walls. They areregarded by some as constitutinga rudimentary prothallus and byothers as a second egg apparatuswhich no longer functions as such.One of the four nuclei at eachend passes to the centre of themegaspore. These fuse and afterfertilization, this, the second-ary nucleus develops the endo-sperm. It is an advantage fo
RMPG173C–. Studies in fossil botany . Paleobotany. 188 STUDIES IN FOSSIL BOTANY the megaspore and prothallus from a fructification, provisionally named Mazocarpon, distinguished by the. Fig. 77.—Lejiidostrobus Vclthehnianus. Megaspore in section, filled with prothallus, which protrudes somewhat through the opening of the megaspore-wall. X 50. S. Coll. 912. R. S. fact that the megaspores in the sporangium are em- bedded in a massive parenchymatous tissue. In other specimens traces of the archegonia are recognisable. M.. Please note that these images are extracted from scanned page images that may have b
RF2A5NNYP–Leafy Xanthoria lichen,from the Greek 'xanthos' meaning yellow. Nitrogen loving lichen, indicates Nitrogen pollutants.Punctelia subrudecta in corners.
RM2AJ3GY1–Recueil des travaux botaniques néerlandais . Position of the Embryo in the Prothallus.The Suspensor. According to Lyon (24), the position of the embryo is deter-mined by the suspensor, which develops first and later givesrise to the embryo (See also Bower (3)). He gives a figure ofthe young sporophyte, m which the suspensor is immediately. Fig. 3. connected with the neck of the archegonium. The position ofthe suspensor, however, varies considerably in the plants in-vestigated, as Fig. 3 shows. In plant 4, which is represented by a transverse section, theposition of the suspensor is almost as i
RMPG2E5T–. Class-book of botany : being outlines of the structure, physiology, and classification of plants ; with a flora of the United States and Canada . Botany; Botany; Botany. Bepatica!. SM, Marchantia, sterilo plant. 524â5, Fortilo plant. 520, Vertical section of the fertil-receptacle ; 527, of a perianth, showing the sporango bursting, 523, One of the clatora with four spores. 529, Portion of it highly magnlfled. of the flowering plants. In the mosses, liver- worts, etc., they appear only on the full-grown plant; in the ferns, Equisetacese, etc., they ap- pear only on the prothallus, the earlies
RF2A53C6P–Pale grey lichen ( Lecanora campestris subsp. campestris ) on a horizontal gravestone. Lecanoraceae
RM2AJ5KBK–The treasury of botany: a popular dictionary of the vegetable kingdom; with which is incorporated a glossary of botanical terms . onsequently unattached, and various-ly shaped and sculptured. They consist oftwo coats containing a grumous mass.On germination the outer coat bursts, andthe inner is elongated and protruded, andby cell-division becomes converted into athin marchantiform frond or prothallus.On the under-surface of the prothallus, twokinds of bodies are borne, one of which,the antherid, produces spiral ciliated sper-matozoids, while the other, which formsthe archegone or female cell,
RMPG173A–. Studies in fossil botany . Paleobotany. Fig. 77.—Lejiidostrobus Vclthehnianus. Megaspore in section, filled with prothallus, which protrudes somewhat through the opening of the megaspore-wall. X 50. S. Coll. 912. R. S. fact that the megaspores in the sporangium are em- bedded in a massive parenchymatous tissue. In other specimens traces of the archegonia are recognisable. M.. Fig. 78.—Mazocarpon, Benson in MS. Isolated megaspore filled with prothallus. X about 35. From a photograph by Mr. W. Tarns. S. Coll. 1756. Renault found megaspores of a Lepidostrobus in which the prothalloid tissue con
RF2A53CFD–Pale grey lichen ( Lecanora campestris subsp. campestris ) on a horizontal gravestone. Lecanoraceae
RM2ANDGE6–Organography of plants, especially of the archegoniatae and spermaphyta . Fig. 152. Vittaria. 1-6, Formation of protliallus ; Ar, arcliegonia; E, embryo ; Br, gemmae,magnified. The others slightly magnified. I, highly margin passing into a permanent condition, and thus there is developeda highly irregular lobed body in some ways resembling the flat protonemaof Sphagnum, and it forms marginal groups of archegonia which, primarilyarising in the meriscem, are separated from it at a later time by the portionswhich have passed into the permanent condition. Hymenopliyllum. The form of prothallus of
![. Studies in fossil botany . Paleobotany. SEED-LIKE LYCOPODIACEOUS ORGANS 195 in at the top, but leaving a narrow crevice or micropyle (Figs. 81 and 82). This opening, however, differed from the micropyle of ordinary seeds in not being tubular, but forming a long narrow slit, extending in the radial direction almost the whole length of the sporangium,. Fig. 81.—Lepidocarpon Lomaxi. Upper part of integumented "seed," containing prothallus. z", integument; sin, wall of sporangium; mg, membrane of megaspore ; pr, tissue of prothallus ; y, possible central cell of an archegonium; c. Stock Photo](https://c8.alamy.com/comp/PG1734/studies-in-fossil-botany-paleobotany-seed-like-lycopodiaceous-organs-195-in-at-the-top-but-leaving-a-narrow-crevice-or-micropyle-figs-81-and-82-this-opening-however-differed-from-the-micropyle-of-ordinary-seeds-in-not-being-tubular-but-forming-a-long-narrow-slit-extending-in-the-radial-direction-almost-the-whole-length-of-the-sporangium-fig-81lepidocarpon-lomaxi-upper-part-of-integumented-quotseedquot-containing-prothallus-zquot-integument-sin-wall-of-sporangium-mg-membrane-of-megaspore-pr-tissue-of-prothallus-y-possible-central-cell-of-an-archegonium-c-PG1734.jpg ". Studies in fossil botany . Paleobotany. SEED-LIKE LYCOPODIACEOUS ORGANS 195 in at the top, but leaving a narrow crevice or micropyle (Figs. 81 and 82). This opening, however, differed from the micropyle of ordinary seeds in not being tubular, but forming a long narrow slit, extending in the radial direction almost the whole length of the sporangium,. Fig. 81.—Lepidocarpon Lomaxi. Upper part of integumented "seed," containing prothallus. z", integument; sin, wall of sporangium; mg, membrane of megaspore ; pr, tissue of prothallus ; y, possible central cell of an archegonium; c. Stock Photo")
RMPG1734–. Studies in fossil botany . Paleobotany. SEED-LIKE LYCOPODIACEOUS ORGANS 195 in at the top, but leaving a narrow crevice or micropyle (Figs. 81 and 82). This opening, however, differed from the micropyle of ordinary seeds in not being tubular, but forming a long narrow slit, extending in the radial direction almost the whole length of the sporangium,. Fig. 81.—Lepidocarpon Lomaxi. Upper part of integumented "seed," containing prothallus. z", integument; sin, wall of sporangium; mg, membrane of megaspore ; pr, tissue of prothallus ; y, possible central cell of an archegonium; c.
RM2ANDNGJ–Organography of plants, especially of the archegoniatae and spermaphyta . inst the gnawing of animals. The Dicksonieae furnish a transition tothe hair-formations of the Cyatheaceae. In them, both upon the upper andunder side, as well as upon the edge of the prothallus, there are gland-hairswhich have a basal foot-cell out of which a cell-row, sometimes branched,develops. Exceptions to the usual heart-like outline of the prothallus arefound in some epiphytic Polypodiaceae, as well as in the Vittariaceae ^ andspecies of Anogramme. These epiphytic forms have long band-like pro-thalli with no cush
RM2ANDH50–Organography of plants, especially of the archegoniatae and spermaphyta . onecycle of affinity, although, at the same time, it isa matter of indifference from the point of view ofthe manner of life which of them obtains. Thatthe heart-like outline of the prothallus is alwaysfinally attained to, although by different ways inthese forms, may find its explanation in this, itis a beneficial configuration. The wings lieloose, seeing that they develop no rhizoids,upon the surface of the soil, and under themdrops of water collect^ (Fig- I5i)> which then canbe readily absorbed by the middle portion
RM2ANDTRE–Organography of plants, especially of the archegoniatae and spermaphyta . i ; the remainder andlarger portion of the interior is divided by two oblique walls inclined towardsthe long axis of the spore into two flat cells, and a third which in opticallongitudinal section is tri-angular. I consider this lastone alone to be the anthe-ridial mother-cell-. It dividesby a periclinal wall into anouter cell, the opercular cell,Z>, and an inner cell, out ofwhich the four mother-cellsof the spermatozoids arise by?division. We should havethen a prothallus consistingof three sterile cells andone anther
RM2AFJEHD–. The Bible and science. FtG. 163.—1. Egg of Hylodes martinicensis, twelve days old. lower surface;2. Young of Hylodes as it leaves the egg; c, tail. b. Adult male Hylodes,natural size. and that of a fern. The spore of the fern developsfirst into a prothallus, from which a plant resemblingthe parent arises, whereas in the lycopod the prothallusis developed in the spore itself, so that the plantresembling the parent springs at once from the spore. In figs. 104 and 165 w^e have diagrams representingthe development of an ascidian and of an amphioxus. MOLLUSC
RM2ANDCE9–Organography of plants, especially of the archegoniatae and spermaphyta . l, Ober die Jugendzustande der PHanzen, in Flora, l.Kxii (1889^, p. 21.^ This term of Bowers is preferable to fruit-shoot, the one I used earlier. RELATIONSHIPS TO WATER. TUBERS 217 Anogramme leptophylla ^ are somewhat more complex. Its sporophyte isannual, as is that of A. chaerophylla. The prothallus, like that of A. chaero-phylla, is a spathulate cell-surface which is funnel-shaped and not flat(Fig. 159) and which can branch and form lobes somewhat after thefashion of that in Vittaria. The tuber-like archegoniophore,
RM2ANDJNF–Organography of plants, especially of the archegoniatae and spermaphyta . Fig. 145. Polypodium obliquatum.Prothallus seen from below. On themargin are bristle hairs and rhizoids,IVh. On the surface two groups ofarchegonia surrounded by rhizoids. Itis only at the points where these groupsare that the prothallus is many-layered.Magnified. Fig. 146. Apex of a band-like prothallus with bristle hairs. Oneof these bristle hairs shows a spiral line of rupture the result of swellino-in potash solution. Highly magnified. their free propagation by gemmae which will be presently mentioned ^ mayalso be co
RM2ANDF9K–Organography of plants, especially of the archegoniatae and spermaphyta . Fig. 155. Salvinia natans. /, megaspore germinat-ing; , archegonium; sk^ apical ridge. //; prothallusisolated seen from above ; three archegonia and themother-cell, ;«, of a fourth are visible ; sk, apical ridgeof meristem ; /% position whence the wings are de-veloped. Magnified. / After Pringsheim. // AfterBauke. Fig. 156. Salvinia natans. Germinated megaspore;prothallus and embrj-o in longitudinal section in the medianline of the prothallus. i^if, portion of wall of sporangium :/, perinium ; c, exine; j, cavity of the
RM2AJ3H3B–Recueil des travaux botaniques néerlandais . exammed some of Lyons slides and published a shortof the embryology of the (orm. A detailed embryo- logical investigation of this form by Campbell is in press (11).The majority of the young plants proves to be still attached to the prothallus (Fig. 1); two were already free (Fig. 2). The size vaned from 1—20 mm. The developmental range was be- tween those in which the second root (and fourth leaf) were making their appearance.. Position of the Embryo in the Prothallus.The Suspensor. According to Lyon (24), the position of the embryo is deter-mined b
RM2ANDJW8–Organography of plants, especially of the archegoniatae and spermaphyta . Fig. 145. Polypodium obliquatum.Prothallus seen from below. On themargin are bristle hairs and rhizoids,IVh. On the surface two groups ofarchegonia surrounded by rhizoids. Itis only at the points where these groupsare that the prothallus is many-layered.Magnified. Fig. 146. Apex of a band-like prothallus with bristle hairs. Oneof these bristle hairs shows a spiral line of rupture the result of swellino-in potash solution. Highly magnified. their free propagation by gemmae which will be presently mentioned ^ mayalso be co
RM2ANDF0D–Organography of plants, especially of the archegoniatae and spermaphyta . ungsgeschichte des weiblichen Vorkeimes bei den heterosporeii Lvco-podiaccen, in Botanische Zeitung, liv (1896), p. 160. Adventitious shoots also appear in Lycopodium Phlcgmaria. • See Tart I, p. 49. * Buchtien, Entwicklungsgeschichte des rrothallium von Equisetum, in Bibliotheca Botanica, viii(iS87),p. 24. 214 ASEXUAL PROPAGATION OF THE PROTHALLUS of Lycopodium, and also in many Hymenophyllaceae and Vittariaceae, andthus, as in the Hepaticae, formation of gemmae has arisen frequently andindependently in different series
RM2AND286–Organography of plants, especially of the archegoniatae and spermaphyta . the pro-thallus. The arrang-ement resembles somewhat that of Isoetes. but is. spm Fig. 176. Selaginella Martensii. Female pro-thallus, pr^ projecting from the ruptured wall, spin, ofthe megaspore ; ar, sterile archegonium ; etnb, embn.two eiiibryos embedded in the tissue of the prothallus;ct, et, suspensors. Magnified 124. Adjusted afterPfeffer. Lehrb. See Part I, p. 220. ? See Jeffrey, The (Jametophyte of Botrychium viri^iniaiuim, Studies from the University of Toronto,Biological Series, 1S98. ?? See Pruchmann, Ober di
RM2ANDPAY–Organography of plants, especially of the archegoniatae and spermaphyta . Fig. 140. Lycopodium inundatum. i, few-celled prothallus ;/?, basilar cell. 2, prothallus with antheridium, ^«; i/, injuredcell. 3, older prothallus with antheridia, Aft, and meristem, MU, injured cell; b, basilar cell. 4, prothallus with archegonia, A,and an embryo showing cotjdedon, Co, and protocorm, B. Allmagnified ; after De Bary. Fig. 141. Lycopo-dium.inundatum. Pro-thai us with arche-gonia, A. ^lagniCed. deal with an inherited character from a primitive chlorophyllous prothallusor with a condition produced by int
RM2AN7RN4–Lectures on the physiology of plants . as it were cut off, furthercell-divisions occur in the remaining cells which constitute together, so to speak, areduced antheridium. This is well seen in I): each of these small cells gives rise toan antherozoid of very simi)le form, just as in the Mosses. Reluming to the germinating macrospore again, it is to be noticed that the 750 LECTURE XLII. true prothallus is separated off from the large spore-cavity by the diaphragm d d: inthis cavity there arises a large-celled tissue, such as we shall meet with later in theembryo-sac of flowering plants—the so-c
RM2AX1YX2–The elements of botany for beginners and for schools . Fig. 509. A young prothallus of a Maiden-hair, moderately enlarged, and anolder one with the first fern-leaf developed from near the notch. 510. Middle por-tion of the young one, much magnified, showing below, partly among the rootlets,the antheridia or fertilizing organs, and above, near the notch, three piatiUidia,to be fertilized. 160 CRYPTOGAMOUS OR FLOWERLESS PLANTS. [SECTION 17. closely resembles a small Liverwort. This is named a PEOTHAliUS (Tig.509): from some point of this a bud appears to originate, which producesthe first fern-l
RM2AFJEBH–. The Bible and science. FtG. 163.—1. Egg of Hylodes martinicensis, twelve days old. lower surface;2. Young of Hylodes as it leaves the egg; c, tail. b. Adult male Hylodes,natural size. and that of a fern. The spore of the fern developsfirst into a prothallus, from which a plant resemblingthe parent arises, whereas in the lycopod the prothallusis developed in the spore itself, so that the plantresembling the parent springs at once from the spore. In figs. 104 and 165 w^e have diagrams representingthe development of an ascidian and of an amphioxus. MOLLUSC. Fjg. 164.—Development of an Ascidian.
RM2AJ3GMJ–Recueil des travaux botaniques néerlandais . the second leaf not yet developed. Photo- graph I shows a young plant with the suspensor. The nextpenodof development Is one in which the first root is very much elongated. The three plants which represent this stage ail show a similar position of the suspensor attached at a much lower place. In ail the cases exa- mined, the root emerged from thelower surface, the cotylédon (a little later) from the uppersurface of the prothallus. There does not seem to be a definite relation between thesuspensor and the position of the first leaf. In Lyon s photo-g
RM2AJ3E27–Recueil des travaux botaniques néerlandais . isible. A single vascular strand connectsroot and leaf. The position of the embryo m the prothallus is, as far ascould be seen, quite the same as that in B. lunaria. The only im-portant différence between this form and B. simplex up to thisstage is the large size of the first leaf in the latter. No trace ofa vascular bundle appears m the cotylédon at this stage. Theinitiais of the cotylédon could not be traced with any certainty. The Formation of the Stèle.The second root makes its appearence at the same place asin B. lunaria. A séries representing
RM2AX2074–The elements of botany for beginners and for schools . Fig. 509. A young prothallus of a Maiden-hair, moderately enlarged, and anolder one with the first fern-leaf developed from near the notch. 510. Middle por-tion of the young one, much magnified, showing below, partly among the rootlets,the antheridia or fertilizing organs, and above, near the notch, three piatiUidia,to be fertilized. 160 CRYPTOGAMOUS OR FLOWERLESS PLANTS. [SECTION 17. closely resembles a small Liverwort. This is named a PEOTHAliUS (Tig.509): from some point of this a bud appears to originate, which producesthe first fern-l
RM2AX1XWJ–The elements of botany for beginners and for schools . spore-cases of two kinds,intermixed. The larger ones contain each a large spore, or macrospore;the smaller contain numerous microspores, immersed in mucilage. Atmaturity the fruit bursts or splits open at top, and the two kinds of sporesare discharged. The large ones in germination produce a small prothallus;upon which the contents of the microspores act in the same way as inPerns, and with a similar result. 496. AzoUa is a little floating plant, looking like a small Liverwort orMoss. Its branches are covered with minute and scale-shaped l
RM2AN7XCH–Lectures on the physiology of plants . Fig. ^?2Z.—.4dia)itum CapiUus-Veneris. Vesection through the prothalUis pp and the young Feli root-hairs; a archegonia; b first leaf, lu first roembryo (x about lo).. FIG. i,ir)..ldHtnti(m CapiUmfirst leaf; iV primary i Prothallium seen from below // with the young Iicondary root; h root-hairs of prothallus (x about i the first year, however, though it produces from its lower leaf-sheaths a few lateralshoots, which penetrate downwards into the soil to continue the growth.next year,since the plantlet arising directly from the embryo itself perishes in the
RM2AN7Y3B–Lectures on the physiology of plants . Fig. 426 ertical section of the lobes of a vigorous female prothallus of Hquisetum at-vensc(after Hofmeister). At aaa two barren and onefertilised archegonium; h root-hairs (X about 60). FIG. 4=7.-Developn,ent of the embryo of H.,uisctum arvense (after Hofn.e.ster). -? v>:rt.cal section ofarchegoniim a with e.l.bryoyiX =00). B a free en.bryo further developed: Ö UK.p.ent «- --« i^-^^-J the first shoot (X =00). C vertical section of a lobe of a prothallus//w.th a young i-/«»./;»«. «.its first root,b b its leaf-sheaths (X 10). what is the same thing, th
RM2CE4K7P–. Evolution of plants . ea of their average dimensions.Megaspores are extremelyabundant in some kinds ofcoal. Very commonly the mega-spores were covered withbristles, among which weoften find the microspores ,entangled; this may havebeen a means of ensuringthat the two kinds of sporesgerminated together. In some favourable cases dendron Vdtheimianum. Megaspore filled with the preservation is so good the prothallus, x 25; that the prothallus is Still (B) archegonium from . another prothallus of the found within the megaspore same plant, x 140; (C) (see fig. 21, A). It consisted archegonium of
RM2CE4KGB–. Evolution of plants . borne in four rows;their margin is fringed with hairs, and on theupper surface is a remarkably well-developedligule. The structure of the stem is much likethat of one of the simpler species of Selaginella. The fructifications are grouped in a loose cone;on the upper surface of each sporophyll is asporangium, containing a single megaspore oflarge size, which occupies the whole cavity of thesporangium, like the embryo-sac in a seed (seefig. 19). The prothallus in the megaspore issometimes preserved. The megasporangium isenclosed in an envelope or coat, by which it iscompl
RM2CE2NKX–. Plants and their uses; an introduction to botany . oduced four tiers of nuclei, all but theuppermost four being enclo.sed in cell-walls. G, .same, after the middletier of cells has elongated to form a suspensor which has pushed thelower tiers of cell into the prothallus (or endosperm) where they giverise, by repeated cell-division, to an eml)ryo which is fed by the endo-sperm. The nutritious materials left over in the endosperm when theoule has become a seed constitutes the seed-food which supports theyoung i^lantlet during germination. (Strasburger.) spreading carpel, they come finally to
RM2CEDXF8–. A popular description of the common Oregon ferns; contribution from the Herbarium of the University of Oregon. nnulusstraightens with more or less of a snap, scattering the spores tosome distance. If the spores meet with favorable conditions they germinate.Plate II illustrates a number of stages of this growth. At first thespore sends out a little root (r) and a short chain of cells (p).These continue to differentiate, becoming flat and leaf-like, Fig. F.This leaf-like form is known as a prothallus and often is a quarterof an inch or more across. The spore disappears, the prothallusbecomes a
RM2CHMH93–. Heredity and evolution in plants . FIG. 19.—Germination of the spores of a fern, a, Before germination;b, early stage, showing protonema (pr.), and first rhizoid (rli); r, d, c, /,successive stages in the development of the prothallus.. !• ic. 20.—Prothallus of a fern. Archegonia on the (central) cushion,near the notch; antheridia among the rhizoids, below. (After MargaretC. Ferguson.) LIFE IIISTOEY OF A FERN 19 firmly to the soil, and also serve to take in water and dis-solved mineral nutrients. 12. The Prothallus.—Before the germ-tube has greatlyenlarged, it becomes divided into two cells,
RM2CHMG1M–. Heredity and evolution in plants . ventral canal-cell; n.c, neck-canal;sp, sperms entering the neck-canal. A and B in longitudinal section. 14. Reproductive Organs: Archegonia.—Examinationof the ventral surface of a mature prothallus with a lenswill reveal near the notch and on the cushion, severaltiny flask-shaped bodies, the. archegonia. Each arche-gonium consists of a wall, one cell thick, and contents(Fig. 21). The neck projects away from the surface 22 HEREDITY AND EVOLUTION IN PLANTS and is usually slightly curved, while the remainder, theventer, is imbedded in the tissue of the cushio
RM2CE2NWB–. Plants and their uses; an introduction to botany . Fig. 370.—Scouring-rush. A, male gametophyte or piothallus (152) show-ing antheridia (a, a). B-E, spermatozoids of various ages, muchmore highly magnified. (Hofmeister, Schacht.) Fig. 371.—Scouring-rush. Female gametophyte or prothallus (^1^-) showingarchegonia (a, a, a) and pseudo-roots (h). (Hofmeister.) in a cone-like aggregation of whorled sac-leaves. Each ofthese has a stalk ending in a shield-shaped expansion, six-sided from pressure. Behind each angle of the shield is alarge sporangium dehiscing by a longitudinal slit (3, 4)-The spore
RMRH946C–. Botany; an elementary text for schools. Plants. (fllnp'^tm 312. Prothallus of a fern. Enlarged. Archegonia at a; antheridia at 6.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Bailey, L. H. (Liberty Hyde), 1858-1954. New York, Macmillan Co.
RMRPX779–. The algae. Algae. plantule 2x cx r ^9 L. ^i- plethysmothallus 2X f B prothallus X plantule 2x. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Chapman, V. J. (Valentine Jackson), 1910-. London, Macmillan; New York, St. Martin's Press
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