86 STATES OF INSECTS. (Lgg.) 
egg of these very minute moths Reaumur had ever an 
opportunity to observe?. 
Other insects, belonging to the tribe which lay their 
eggs singly, bury them in the ground. Of this descrip- 
tion are many of the petalocerous beetles, the dung- 
chafers (Scarabeide) particularly, which, inclosing their 
egos in a pellet of dung, deposit them in deep cylin- 
drical cavities. Concerning the proceedings of some 
of these, as well as of the whole race of bees, wasps, &c., 
which all lay single eggs, I have before detailed to you 
many interesting particulars>. I must not conclude this 
subject without observing, that the female Pycnogonide, 
an osculant tribe between Insects and Crustacea, carry 
their eggs upon two pair of false legs*. 
iii. Substance. From this long dissertation on the sztu- 
ation of the eggs of insects and matters connected with it, 
I pass on to their substance or their external and internal 
composition, giving at the same time some account of the 
embryo included in them. The eggs of insects, like those 
of birds, consist in the first place of an external coat or 
shell, varying greatly, as to substance, in different genera. 
Most commonly, particularly in those which deposit their 
egos in moist situations, as in dung, earth, and the like, 
it is a mere membrane, often thin and transparent, and 
showing, as in spiders, all the changes that take place in 
the inclosed embryo, as the formation of the head, trunk, 
and limbs*.” This membrane is sometimes so delicate as 
to yield to the slightest pressure, and insufficient to pro- 
a Reaum. i. 8—. > Voz. f. 350—. 372—. ~ 
© N. Dict. d Hist. Nat. xxviii. 271. * De Geer vii. 194. 
