RMRHKJBA–. The Biological bulletin. Biology; Zoology; Marine biology. DEVELOPMENTAL RATE AND TEMPERATURE 75 it is of some interest to examine how well two of the commonly em- ployed formulae fit our data. We shall consider first the Arrhenius equation which has been extensively applied by Crozier and his col- laborators (1924-) to various biological processes including the rate of development. If the logarithm of the velocity of the particular process is plotted against the reciprocal of the absolute temperature, then, according to the Arrhenius equation, a straight line should be expected. In the grap

RMRHM7KB–. The Biological bulletin. Biology; Zoology; Marine biology. 224 O. C. GLASER. Here too Osborn found hiatuses, but if these really occurred in the living state, it is difficult to see how a sac with holes in both its inner and outer linings could contain the eggs which these larvae ingest. When the fully gorged cannibals transform into veligers, the changes undergone by the entoderm are as striking as those in the external form of the larvae. These changes lead to regional differentiation, the outcome of which is that the dorsal cells of the digestive tract come to be very unlike the ventral o

RMRHM6EB–. The Biological bulletin. Biology; Zoology; Marine biology. CYCLE OF PHOSPHORUS IN GULF OF MAINE 441 Methods of estimating its value are so indirect that little is known of its magnitude under any circumstances. Although our data are admittedly very unprecise and yield only minimal values for the exchange, it is nevertheless of some interest to use it in estimating the coefficient required to account for the transport of phosphate in the Gulf of Maine. The gradient of phosphate concentration is sufficiently uniform throughout the period May-November to permit a single value to be taken at any

RMRHM78M–. The Biological bulletin. Biology; Zoology; Marine biology. 244 C. W. METZ Several cases have been examined in which an expanded region in one chromosome has adhered to the side of another chromosome and the two have then been pulled apart when the cell was crushed. In such cases that part of the expanded portion which is subjected to tension shows a realignment of materials to form striations, focusing at the point of adhesion. In some of these cases similar rearrangement of materials and focusing of the striations has been effected in the other. Fig. 4. Illustrating the distortion effect of

RMRHKK2N–. The Biological bulletin. Biology; Zoology; Marine biology. COPPER, ENZYMES, AND FERTILIZATION. 93 These changes become intelligible if we assume, in the one case, the formation of minute traces of copper xanthate; in the second, of copper ferrocyanide. Since the same reagents produce no noticeable changes in these locations in untreated material, it appears that the cortex of an egg exposed to copper contains more than the normal quantity of the metal. Moreover, the excess is localized chiefly near the surface, and since it is not the agglutinin that is copper bearing, but the lipolysin, it

RMRHKHGD–. The Biological bulletin. Biology; Zoology; Marine biology. THE ACTION OF ERGOTAMINE ON THE CHROMATO- PHORES OF THE CATFISH (AMEIURUS NEBULOSUS) Z. M. BACQ1 {From the Marine Biological Laboratory, Woods Hole, Mass.) It is a well-known fact that ergotamine paralyzes the action of adrenalin and the effects of sympathetic stimulation. But ergotamine has also a definite action on the denervated cells, and this action, as far as it has been investigated, is the same as that of adrenalin. Thus ergotamine, in the cat, increases the rate of the denervated heart (Cannon and Bacq, 1931), contracts the

RMRHM3HR–. The Biological bulletin. Biology; Zoology; Marine biology. PROTEIN SYNTHESIS IN SEA URCHIN EGGS 215 activity from the polysome region to the monoribosome region of the gradient after RNase-treatment of the homogenates, particularly of the fertilized eggs; also, pre- treatment with RNase-free trypsin has sensitized the unfertilized egg aggregates to dissociation by RNase. 4. Autoradiography of unfertilised eggs The presence of labeled protein in unfertilized sea urchin eggs that had been exposed to radioactive amino acids has been demonstrated autoradiographically in previous investigations (

RMRHG8Y5–. The Biological bulletin. Biology; Zoology; Marine biology. THE SACRUM OF THE LACERTILIA. 87 very short. They arise broadly from the centra of the vertebrse. The same may be said of the adult specimen. In the Phrynosoma specimens a nearer approach to the ancestral condition of the vertebrate sacrum is seen. Gegenbaur (13) is of the opinion that the sacrum of the vertebrates was primitively of but one vertebra. Fig. 1. Skeleton of Phrynosoma douglassi hernandesi. Girard. as is found in the modern amphibians. Such a condition is what would be expected. In Phrynosoma the first sacral vertebra be

RMRHM27R–. The Biological bulletin. Biology; Zoology; Marine biology. 416 PER HALLDAL photooxidation at all intensities applied. Samples taken from layers or patches of Ostreobium below the layer nearest the surface did usually not respond to light. In some few cases photooxidation was observed. Action spectra. Action spectra of both photosynthesis and photooxidation could be performed. In the case of photooxidation the reduction in /'Og was re- versible with gentle doses of irradiation. Because of this, action spectra of photo- oxidation could be recorded with the field apparatus, though corrections a

RMRHM6W4–. The Biological bulletin. Biology; Zoology; Marine biology. DETERMINATION IN CEREBRATULUS EMBRYO 321 were stained, the upper, most animal part of the whole band (with one probable exception, see below) contained blue granules, and when the vegetative cells had been stained, the color was restricted more or less to the lower, vegetative part of the band. It is very difficult to trace the limit of the stained area with certainty in Cerehratulus, but I think it is evident that the ciliated band is composed of material both from the animal and the vegetative cells. It was observed in several case

RMRHM6H1–. The Biological bulletin. Biology; Zoology; Marine biology. A MICROSCOPE-STAGE INCUBATOR. 325 incandescent to the egg-cell, but also increases the size of the bulb, and thus increases the sensitivity of the regulator. For my purpose, the regulator is adjusted so as to maintain a temperature of about 39.40 C. in the neighborhood of the ther- mometer t, which is placed as close to the egg-cell as will permit an easy manipulation of the objectives. In order to keep the temperature constant it is necessary to have a circulation of the. Fig. 1. water within the incubator, and the way in which this

RMRHM4TC–. The Biological bulletin. Biology; Zoology; Marine biology. ENDOCRINES AND CRAYFISH GROWTH 259 that the rate of synthesis of the hormone was reduced below the rate of transfer. Since the type 2 cells are probably the source of the molt-inhibiting hormone and since the implantation of eyestalks inhibits the premolt growth stage of limb regeneration in crabs (Bliss, 1956), it is logical to assume that the presence of stainable material in the type 2 cells, during the intermolt period when molt- inhibiting hormone hypothetically is released, indicates that these cells are actively synthesizing t