274 CLA YPOLE. [VoL. XIV. 
corresponding to the parts of the adult. The yellow material 
in the sac-like parts of the organs is yolk (Fig. 64, y.), and the 
golden yellow globules scattered through the connective tissue 
is yolk acquiring the characters of fat globules. The whole 
body is very simple in structure, a few muscle fibres, the ven- 
tral nerve chain, and a large amount of connective tissue filling 
up the space being the essential elements; numerous blood 
corpuscles loaded with yolk present in the small body cavity 
were not represented in the figure. The reproductive organ is 
shown at a later stage of development in Fig. 65 in frontal 
section; the yolk has been absorbed from that part of the sacs 
near the germinal epithelium, and by rapid proliferation, prob- 
ably rendered possible by the ample supply of food, very small 
sperm cells are being formed that will eventually mature as 
spermatozoa; these fill the sac. 
In Figs. 59, 60, and 62 the story of the first group of 
germinal cells originating within the cavity of the somite is 
continued. Fig. 60 represents a cross-section of an ovary from 
a recently hatched or at least very young Anurida. The cut 
does not include the germinal epithelium, but some of the cells 
that have become detached from it are figured that show char- 
acters rendering their recognition easy. At z.c. are cells that 
bear all the distinctive marks of nutritive cells, large nuclei, 
richly supplied with chromatin, which is irregularly massed 
together, but not stellate in arrangement. At o. are seen cells 
that as distinctly possess the characters of ova, large cell body, 
and small clear nucleus. Scattered among these are gran- 
ules of true embryonic yolk of irregular sizes. This is even 
included in some of the ova, as shown in Fig. §9. The ovarian 
wall is extremely thin; small nuclei occur at intervals that 
closely resemble the mesodermic nuclei of younger stages. 
Fig. 61 is a representation of an ovum with its nutritive cells, 
as found in an animal taken early in the summer, evidently 
before development had begun for the season. This shows 
how little, excepting in one respect, the ova and nutritive cells 
change during the winter. The one respect is in the chromatin 
of the nutritive cells; in the last figure the definite stellate 
structure is attained, while in the younger forms the chromatin 
