. The development of the albino rat, Mus norvegicus albinus. Embryology -- Mammals; Rats. 50 G. CARL HUBER of the two cross diameters. This ma^^ be seen from tlie series of drawings made of a blastodermic vesicle cut cross-wise, taken from the uterus of rat No. 68, from which were also taken the two vesicles shown in D and E of figure 20. This series of figures is shown in figure 21, in which are reproduced in serial order the seven successive cross sections into which the vesicle was cut. It measures 65 n by 38 /x by approximately 70 ,u, and is found at the bottom of a mucosal fold, found at
. The development of the albino rat, Mus norvegicus albinus. Embryology -- Mammals; Rats. 50 G. CARL HUBER of the two cross diameters. This ma^^ be seen from tlie series of drawings made of a blastodermic vesicle cut cross-wise, taken from the uterus of rat No. 68, from which were also taken the two vesicles shown in D and E of figure 20. This series of figures is shown in figure 21, in which are reproduced in serial order the seven successive cross sections into which the vesicle was cut. It measures 65 n by 38 /x by approximately 70 ,u, and is found at the bottom of a mucosal fold, found at the mesometrial border, and is resting with one side on the epithelial lining of a shallow pit, the other wall of this mucosal fold, also showing a shallow pit, is slightly retracted. From a study of this series. 000 Fig. 21 A complete series of cross-sections of an earh' stage of blastodermic vesicle of the albino rat. X 200. Rat No. 68, 4 days and 16 hours. A to C, sections through roof of vesicle, showing segmentation cavity; D to G, sections through floor of vesicle. of sections, I feel certain that the plane of section is cross and not oblique to the long axis of the vesicle. The roof of this vesicle passes through three sections, A, B and C. The segmentation cavity has thus a depth of less than 30 fx. The overlapping of the cells surrounding the segmentation cavity is to be noted, especially as seen in B of this figure. This arrangement of the cells may explain how the cavity may be enlarged without a material increase in the number of the enclosing cells—in part, by a flattening out of the cells, in part by a rearrangement of the relations of the cells. In the figures of the sections passing through the floor of this vesicle, D to G, attention is drawn to the size, form and relations of the cells and to the fact that there is no distinct covering layer. In this series of sections, there are. Please note that these images are extracted from scanned page images that may
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Keywords: ., bookcontributorgerste, bookpublisherphiladelphiapa, bookyear1915
