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POPULAR SCIENCE REVIEW. 
normal process of development. Each ovum produces an embryo 
without previous fertilisation. The parent larva undergoes no 
metamorphosis, and never becomes a perfect insect. It may, 
however, transform itself into an inactive nymph, enclosing the 
young brood when completely grown. The evolution and growth 
of the ovum and its embiyo goes on at first at the expense of 
the parent larva’s circulating fluid, afterwards by absorption 
of the nutritive matter previously amassed in the fatty tissue. 
Finally, when the embryos are liberated from their egg-cover- 
ings, they feed on the viscera of the dead parent. The genera- 
tion so produced, reproduces in its turn other generations. Pa- 
genstecher concludes, that this form of non-sexual reproduction 
is similar to that of the aphis, and that a germ-producing organ 
will be discovered by further observation. 
4. In the month of March, 1865, M; Ganine announced, in 
a paper read before the Academy of St. Petersburg, that he 
had found in the worm-eaten planks of buildings, and in worm- 
eaten pasteboard, wood, and in other places, larvae similar ta 
those examined by Wagner and Pagenstecher, which, holding a 
middle place between these, differed slightly in appearance, but 
which- propagated in the same way. M. Ganine verifies the 
surmise of Pagenstecher respecting the existence of a special 
reproductive organ. He found that the germs or ovules were not 
generated in or by the fatty tissue, but that they proceeded from 
small sacs, which he calls ovaries. These organs, two in number, 
are! placed symmetrically on either side of the median line, at the 
eleventh segment of the body of the young larva, and lodged in 
a small recess excavated on the inner edge of the fatty tissue. 
Each “ ovary” is formed by a thin transparent sac, of an oval 
shape, intimately adherent to the fatty tissue. The sac is filled 
with a clear fluid, containing a few granules, and two or three 
small cells. As the larva grows its ovaries increase in size also, 
and become detached from the surrounding tissue, with which 
they remain connected only by two fine filaments. Whilst this 
change of size occurs, germs or “ pseud ova ” are developed. 
First of all, the granular contents multiply, and form corpuscles 
b} T aggregation. Some of these corpuscles are transformed into 
cellules, by being grouped together and enclosed in a mem- 
branous envelope. These cellules are seen, at first, only on the 
side of the ovaiy, projecting as half circles : by degrees they 
enlarge, and, amidst the doubly outlined granules which fill 
them, a single larger one may be seen which represents the 
“ germinal vesicle,” with its nucleus. This disappears at a 
later period, or is confounded with other granules. In the 
subsequent development each young u pseud ovum ” is covered 
with a thick viscid refractive layer; but the development does 
not go on contemporaneously in all the cellules, or equally in 
