STATES OF INSECTS. (/igg.) 91 
all of the same size; but in several tribes, those con- 
taining the germe of the female are larger than those that 
are to give birth to a male. This appears to be the case 
with those of the Rhinoceros beetle (Oryctes nasicornis*), 
and according to Gould with those of ants®. As the 
female in a vast number of instances is much bigger than 
the male, it is not improbable that this law may hold 
very extensively. It is stated, however, by Reaumur‘, 
that the reverse of this takes place in the eggs of the 
hive-bee, those that are to produce males being larger 
than the rest. : 
Another peculiarity connected with the present head 
is the augmentation in bulk which takes place, after ex- 
clusion, in the eggs of the great tribe of saw-flies (Ser- 
rifera), the gall-flies (Cynzps), the ants (Formicarze) and 
the water-mites (Hydrachna). Those of the two former, 
which are usually deposited in the parenchymous sub- 
stance of the leaves, or of the young twigs, of various 
plants, imbibe nutriment in some unknown manner, 
through their membranous skins, from the vegetable 
juices which surround them*, and when they have at- 
tained their full size are nearly twice as large as when 
first laid. Except in the eggs of fishes, whose volume 
in like manner is said to augment previously to the ex- 
trusion of the young, there is nothing analogous to this 
singular fact in any other of the oviparous tribes of ani- 
mals, the eggs of which have always attained their full 
size when they are laid. 
It is to M. P. Huber that we are indebted for the 
knowledge of the fact that the eggs of ants grow after 
being laid, a circumstance favoured probably by the 
@ Bibl. Nat. i. 132, b. » Gould 36. 
© Reaum, v. 477. ¢ Thbid. 1. 579. vy. 121, 
