ME. LEBBOCK ON THE OVA AND PSEUDOVA OF INSECTS. 
359 
No one has yet seen a male of C. ]ies])endum, but this presence of the spermatheca 
indicates that this sex does occasionally occur. Whether the spermatheca fulfills any 
other function, as for instance that of a secreting gland, I am unable to assert. 
The colleterial glands are very small in C. hesperidimi^ but in C. jpersicm they are very 
conspicuous. This difierence is probably owing to the fact that the egg-shell is much 
more developed in the latter species than in the former. 
The two tubes of which the ovary consists, and which in old specimens occasionally 
throw off short branches, are by no means homologous with the egg-tubes of other 
insects, but rather with the uterus, or ovarian cavity into which they fall, and the short 
egg-chamber is the true homologue of the egg-tube. 
In its earliest stage the egg-follicle is a simple projection of the ovarian wall, which 
becomes gradually pear-shaped, and may then be seen to consist of a structureless outer 
membrane, a layer of epithehal cells, and three masses bounded by very delicate walls, 
and each containing a large nucleus (Plate XVIII. figs. I, 2). These three masses evi- 
dently represent the vitelligenous cells of other insects, as Leuckart* has correctly 
suggested ; but they are often very indistinct, and in some cases were altogether undi- 
stinguishable, though acetic acid will generally make them visible. They are very seldom 
more than three in number ; indeed I only found four in one or two specimens, and five 
once, out of many hundreds which I examined. Sometimes, indeed, only two or even 
one could be seen ; but it is probable that in these instances the cells were not really 
absent, but were only rendered invisible by their refractive power being nearly the same 
as that of the surrounding medium. After the egg-tube has attained to a certain 
size the boundaries of these cells disappear, as seems to be sometimes the case in 
Hymenoptera and other insects, and the nuclei only remain visible. Each nucleus often 
contains a solid-looking, irregular, greenish body or nucleolus. 
I am inclined to believe that these cells are originally the same as those constituting 
the epithelial layer, but on this point it is difficult to form a decided opinion. Their 
nucleolus is certainly very different, and under the action of water they become cloudy, 
whilst the epithelial cells remain perfectly clear. 
The epithelial cells line the structureless membrane forming the outer covering of the 
egg-follicle. As in other insects, they are columnar in the lower egg-chamber, and 
very much flattened in the upper. They contain a distinct circular nucleus, whose tissue 
differs but little from that of the cell itself, so that they cannot be seen unless they 
are exactly in focus. Plate XVIII. fig. I represents the earliest follicle in which I have 
seen them ; I did not not notice in this case the nuclei, but have no reason to doubt 
their presence. They differ veiy much in size in different specimens, though tolerably 
equal in each, except that they are generally larger in the upper chamber than in the 
lower. W ater causes not only the epithelial cells, but also the whole upper chamber to 
swell considerably. They are originally round, or rather somewhat polygonal from 
mutual pressure, but as the follicle grows they are laterally distended so as to become 
* Loc. cit. p. 366. 
3 B 2 
