270 
(GEOFFREY SMFJ’H. 
iu a peripheral cytoplasmic area, and these globules stain 
bright red, showing that they consist of neutral fat. If an 
ovary be taken at the period when it has recently started to 
form yolk — a period which can be recognised by the pale- 
yellow colour of the ovary — the eggs can be detected in a 
very interesting period of their growth. On one side of the 
-eggs small globules can be seen, lying in a pale-blue cyto- 
plasmic area, which stain bright red, while on the other side 
of the egg these red-staining globules pass through a tran- 
sitional zone into purple-stained yolk-globules of much larger 
size. The nucleus, with its colourless nucleoplasm, dark-blue 
nucleolus and surrounding area of blue cytoplasm, divides 
the two sorts of globules. As the egg increases in size, the 
purple yolk-gl(d)ules go on growing at the expense of the red 
fat-globules, until the latter are confined to a small peripheral 
area surrounding the egg, and to some extent are to be seen 
in the cytoplasmic area round the nucleus. Quite young eggs 
which have not begun to store yolk consist merely of the 
nucleus surrounded by a blue-staining granular cytoplasm. 
It is clear from the observation of these stages that the young 
eggs take up fat from the blood, and deposit it at first in the 
form of neutral fat (red-staining globules), and that these 
neuti-al fat-globules are worked up into the purple-staining 
vitellin or yolk-globules probably by the action of the 
cytoplasm in the region of the nucleus. 
In one case, as the result of a pathological change, the 
reverse of this process was observed, viz. the breaking-down 
of the yolk-globules into neutral fat again. This was found 
in a female infected with a Sacculina which had died before 
coming to the exterior. The ovary of this female consisted 
partly of very young eggs in process of growth, and partly 
of degenerating masses of eggs which had nearly reached 
maturity, but in which the yolk-globnles were being broken 
down to form masses of red-staining neutral fat. In certain 
places this process of degeneration had gone so far that 
nothing remained of the eggs except accumulations of neutral 
fat . 
