356 
ME. LUBBOCK ON THE OVA AND PSEUDOVA OE INSECTS. 
Hymenopterous insect. At first small and round, they become larger in each successive 
egg-chamber, and are gradually forced to take a polygonal form, by the pressure -which 
they mutually exert upon one another. The nucleus continues round, and is somewhat 
darker than the surrounding cell. The -vitelligenous cells in each chamber are not, how- 
ever, all of the same size ; on the contrary, they vary a good deal in this respect, and 
those which lie nearest to the egg-germ are larger than those at the anterior extremitv'. 
The yelk itself is clear, transparent, and contained, in the lower egg-germs of the 
specimen figured, a cloud of reddish-brown granules just behind the geiminal vesicle. 
Ill most specimens, however, I found these granules collected all round the germinal 
vesicle, so as to obscure it very much. The epithelial cells are not much developed in 
Carabus, perhaps o-wing to their function being in part fulfilled by the vitelligenous cells. 
The macula germinativa, as is I believe the case in all insects, has the form of a round 
vesicle. In the second chamber of the figure the germinal vesicle was about -g^ in 
diameter, and the macula about -g^. In the other egg-germs they became gradually 
smaller. The macula germinativa seemed to be composed of a number of small oval 
masses, enclosed apparently by a very delicate membrane. In one case it appeared to 
me as if the macula was broken up, and these little bodies were floating about loose in 
the germinal vesicle. Besides the true macula, each germinal vesicle contained a num- 
ber of smaller vesicles, which seemed to become more numerous in the larger egg-germs. 
They were none of them, ho-v^^ever, nearly so large as the true macula. 
In 8teropus madidm, also, the germinal vesicle contains some of these small vesicles, 
which however are not so numerous as in Carahus violaceus. In young egg-germs of 
Steropus^ two or three of the vesicles are at fii'st sometimes of equal, or very nearly equal 
size. Gradually, however, one of them surpasses the rest, and becomes the macula germi- 
iiativa. Probably, therefore, these small vesicles are of no great functional importance. 
The development of the eggs in the Lepidoptera has attracted the attention of natu- 
ralists more than has been the case in any other order. Heroldt, klETER, Steix, and 
Leuckart have all given more or less accurate figures and descriptions of these organs. 
The type is essentially the same as in the Geodephagous beetles, and difiiers merely 
ill the smaller number of egg-tubes, with a greater number of egg-chambers in each, and 
ill the absence of any terminal chamber. 
As in the Geodephaga, the vitelligenous cells are large and polygonal, and each pre- 
sents a distinct nucleus. The constrictions are deep, but the egg-chambers follow one 
another immediately, without ever presenting any long narrow portion, as in some 
Diptera ; and the yelk-cell grows much more rapidly than in that order. 
In the pseudovaria of Solenohia lichenella the egg-tubes are, according to Leuckart, 
very short, but otherwise the type of formation is precisely the same as in any of the more 
normal orders of the group. The mode of egg-formation exemplified in Plate XVIII. 
fig. 17, except as far as regards the shortness of the tube, is precisely the same as that of 
any other Lepidopterous insect. 
Moreover many instances have been established of unfecundated eggs proving to be 
