jVIE. LUBBOCK ON THE OVA AND PSEUDOVA OE INSECTS. 343 
indefatigable labours of M. Leon Dufoue and others, we are tolerably well acquainted 
with the external form of insect-ovaries, but very few writers have paid any attention to 
the histology and internal structure of these organs. In this country, indeed. Dr. Allen 
Thomson* is almost the only one who has written on this matter, and he was so limited 
in time and space, that he was unable to enter at length into this portion of his subject. 
I propose, therefore, first, to give an account of the process of egg-formation through- 
out the Insecta, and then to describe the pseudova of Coccus, Cynips, and Solenohia, in 
order to show that, as far as we are yet acquainted with these secrets of nature, the two 
processes are perfectly identical. 
In all female insects there are two ovaries, each generally consisting of several egg- 
tubes opening into a common chamber, called the uterus. At its posterior end the uterus 
contracts into the oviduct. The two oviducts converge to the middle line of the body, 
where they unite to form the egg-canal, to which various appendages are usually 
attached. The upper or anterior end of each of the egg-tubes is kept in its place by a 
connecting filament, which is generally attached to the dorsal vessel, either separately 
or after having united with the other filaments belonging to the same ovary. 
The egg originates and generally attains its full size in the egg-tubes, which differ very 
much in different groups of insects. In all the large orders, except perhaps the Lepi- 
doptera and Heteroptera, we find some species in which they are very few, and others 
in which they are very numerous, as, for instance, among Coleoptera, in Lytta vesicato- 
naf; among Orthoptera, in Acheta domestica ; among Neuroptera, in Libellula; among 
Diptera, in the TipulidcB and Culicidce ; among Homoptera, in Coccus ; and among Hyme- 
noptera, in Apis mellijica, which has about 170$. 
On the other hand there are, among the Coleoptera, in Lixus^ and Anthonomus^, only 
two, in Hypophloeus^ and Lathridius porcatus || only three ; among Orthoptera, in which, 
on the whole, they are most numerous, a small species of Locusta had only six ; among 
Neuroptera, Psocus has only five; among Diptera, Melophagus has only two^; among 
Homoptera, Schizoneura corni** and ApMs pcidi** have respectively only two and three ; 
and among Hymenoptera, in Chelonus only two ; and even in Apis mellijica the workers 
have only from two to twelve, the general number being five or sixf'f’. 
A very remarkable instance of this difference occurs in the Forjiculidm, in which fa mil y 
F. auricularia possesses a large number of very short egg-tubes, whilst Labidura gigantea 
has only five, which however are much longer $$. 
According to Buemeistee§§, the ovaries in Fphemera and Stratiomys are s im ple bags 
* Todd’s Encyclopaedia, Article ‘ Ovum.’ 
•f Lacobdaiee, Introduction to Entomology, vol. ii. p. 333. 
X Letjckaet, 1 . c. p. 421. § Eeey and Leucexet, Lehrbucli zur Zootomie. 
II Stein, Der weiblichen Gescblectsorgane der Kafer, p. 27. 
^ Leuckabt, Zur Entwickelung der Pupiparen, p. 8. 
** Letjckaet, 1. c. p. 336. -|-j- Letjckaet, Zur Kenntniss, p. 421. 
See Leon Dtjeoue, Ann. des Sc. Nat. 1828. 
§§ Manual of Entomology, translated by Shtjckaed, p. 184 
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