ox THE FOEMATIOX OF THE EGG IX THE AXXULOSA. 
615 
round the centre, so that the margin is still composed of the clear yelk-substance ; and 
their refrangibility is great, so that they give the egg a peculiar and beautiful appear- 
ance. 
They do not continue to enlarge as they increase in number ; but even when only two 
or three are present, they are often as much as of i^ich in diameter — a size 
which is seldom exceeded even in full-grown eggs. 
The females are provided with a sac, which I think myself justified in calling a 
spermatheca. It opens close to the vulva, is slightly narrowed at the outlet, cylindrical 
in form, and more or less bent at the end, which is double. I always found it full of 
the greenish ovoid spermatozoa. They exactly resembled those found in the testis and 
ductus ejaculatorius of the male, but sometimes seemed to have developed round them- 
selves a cellular envelope. I never found in this organ any filiform spermatozoa. 
Weak acetic acid dissolved the Purkinjean vesicle and macula as usual, but it had no 
efiect on the yelk-globules, nor the intermediate clear yelk-substance. Very dilute 
ammonia also dissolved the macula, and, as above mentioned, at first made the epithelial 
cells more distinct. It did not afiect the yelk-glohules, nor darken the yelk-suh stance, 
but apparently it caused the latter to swell, since, although the wall of the follicle did 
not seem to shrink, the contents were more or less completely ejected from it. It had 
no effect on the yellowish “ corpora lutea.” 
I began to examine CJielifer in the month of August ; and of the first few specimens 
collected nearly one-half had eggs or young ones attached to them^. The eggs were 
seventeen or eighteen in number, and were enclosed in a sort of case, in shape some- 
what resembling a D (Plate XVI. fig. 29). Each egg had a more or less separate com- 
partment ; and they were arranged in one plane, five being generally in the middle, and 
the remainder surrounding them in a single series, the straight border containing four or 
five. The case lay at the lower side of the abdomen, with the straight margin in front, 
and was attached to the body of the animal at or close to the vulva. The case itself 
consists of a transparent structureless substance. 
I met with five specimens in this condition, but, being busy at the time, and expect- 
ing to find others in the autumn, I unfortunately made only a few rough notes. The 
eggs were about of an inch in diameter, and of various shapes. They possessed 
a firm chorion. They underwent a regular yelk-segmentation, but the yelk-spheres by 
no means filled the egg. Tlie eggs in each case were in approximately the same stage of 
development. The most advanced contained eight yelk-spheresf (fig. 28), and also some 
large, clear, transparent vesicles. 
The yelk-spheres occupied about two-thirds of the egg, and appeared to be composed 
of oil-glohules, loosely connected together, and each about of an inch in dia- 
* De Tkeis also found a female of C. cancroides with eggs attached to the under side of the abdomen. 
(Ann. 8c. Xat. 1st ser. vol. sxvii.) 
t This was the case with all the eggs in three of my specimens, and it is remarkable that Grubb never 
found more than eight spheres of segmentation in the eggs of CJlepsine. 
