. Botany; principles and problems. Botany. THE SPERM A TOP 11Y TA 345. 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.. Sinnott, Edmund Ware, 1888-. New York, McGraw-Hill
RMRH8WDN. Botany; principles and problems. Botany. THE SPERM A TOP 11Y TA 345. 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.. Sinnott, Edmund Ware, 1888-. New York, McGraw-Hill
. Botany; principles and problems. Botany. THE SPERM A TOPH YTA 365 Glumales (Fig. 237).—These are the grasses and the sedges. The small flowers lack a typical calyx and corolla, are protected hy chaffy bracts, and are arranged in clusters. They are wind- pollinated, except for those cases where pollination is affected directly, without external agency. As in the Amentiferae, their simple condition may have come about through reduction. The grass family includes the most important of our crop plants.. Fig. 237.—One of the Glumales. A sedge (Carex), belonging to the family Cyperaceae. Fig. 238.
RMRH8W57. Botany; principles and problems. Botany. THE SPERM A TOPH YTA 365 Glumales (Fig. 237).—These are the grasses and the sedges. The small flowers lack a typical calyx and corolla, are protected hy chaffy bracts, and are arranged in clusters. They are wind- pollinated, except for those cases where pollination is affected directly, without external agency. As in the Amentiferae, their simple condition may have come about through reduction. The grass family includes the most important of our crop plants.. Fig. 237.—One of the Glumales. A sedge (Carex), belonging to the family Cyperaceae. Fig. 238.
. Botany; principles and problems. Botany. TIIR SPERM A TOPJI VTA 359 tive corolla, composed of petals; its pollen-producing stamens, and its ovule-bearing pistil. The pistil may be a single carpel (which has grown about the ovules and enclosed them); a number of. /-^ r J • •. 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.. Sinnott, Edmund Ware, 1888-. New York, McGraw-Hill
RMRH8W75. Botany; principles and problems. Botany. TIIR SPERM A TOPJI VTA 359 tive corolla, composed of petals; its pollen-producing stamens, and its ovule-bearing pistil. The pistil may be a single carpel (which has grown about the ovules and enclosed them); a number of. /-^ r J • •. 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.. Sinnott, Edmund Ware, 1888-. New York, McGraw-Hill
. Botany; principles and problems. Botany. THE SPERM A TOPII VTA 347 structure (the stigma) which is nearby. Since the egg cells are buried in the nuccllar tissue, it is evident that the male gametes cannot approach them directly, as in the lower plants, and a new structure has accordingly been developed which conveys them to the egg. This is the pollen-tube. It arises from the pollen-grain as a slender, thin-walled projection and into it the contents of the gi'ain passes, led by the tube-nucleus.. Fig. 218.—Development of the male gametophyte in a gymnosperm (Pine). A, longitudinal section (d
RMRH8WCJ. Botany; principles and problems. Botany. THE SPERM A TOPII VTA 347 structure (the stigma) which is nearby. Since the egg cells are buried in the nuccllar tissue, it is evident that the male gametes cannot approach them directly, as in the lower plants, and a new structure has accordingly been developed which conveys them to the egg. This is the pollen-tube. It arises from the pollen-grain as a slender, thin-walled projection and into it the contents of the gi'ain passes, led by the tube-nucleus.. Fig. 218.—Development of the male gametophyte in a gymnosperm (Pine). A, longitudinal section (d