of the Oil Beetle, Meloé. 303 
development of ova. "This explains the fact of the extreme enlargement of the 
body of the unimpregnated female, in which the first set of eggs have passed 
into the ovaries and are ready for fecundation while a second set are in the 
course of development in the ovisacs. 
The number of eggs deposited at the second laying is always smaller than 
at the first, and at the third and subsequent ones smaller than at the second ; 
since the great object of nature, the continuation of the species, being fulfilled 
in the first instance, the vital and functional powers of the animal begin 
immediately to decline. This occurs with both the sexes. The males soon 
disappear, and the females alone survive for a few weeks after pairing, which 
I believe takes place only once with each female. Those Meloés which are 
seen abroad after the end of April are almost always females, scattered soli- 
tarily over the fields, wandering in quest of food, or of a proper locality for the 
deposition of their eggs, after which they also perish. 
The fecundity of Meloé is sometimes greater than that which I have al- 
ready stated. On the 1st of May 1836 I captured a M. proscarabeeus in the 
act of digging her burrow beneath grass at the side of a footpath. I placed 
her alone in a glass vessel filled with mould and a turf, and she soon began to 
excavate beneath it. Early on the morning of the 5th of May she deposited a 
moderate-sized packet of eggs, and at eleven o'clock came forth again to 
feed, with her body reduced to less than half its previous dimensions. She ate 
voraciously ; and in less than four days her abdomen had again attained its 
former size, and she appeared as though she had not deposited any ova. On 
tbe 12th of May she deposited the second laying, and a few days afterwards a 
third, and on the 25th of May a fourth packet. On each occasion she formed 
her burrow beneath the grass, and always before leaving it covered her eggs 
completely with earth.. This fact of four packets of eggs being deposited by 
the same individual within the short space of twenty-one days is exceedingly 
interesting, and most distinctly proves that one impregnation only is neces- 
sary to fecundate all the eggs a female may produce during her entire life, as 
in this instance there was no intercourse between the sexes. It is interesting 
also with reference to the rapid development of the germ. After each depo- 
sition of eggs the body of the insect was reduced to a small size, and she took 
food with great eagerness; but within a very few days it was enlarged again 
