of the Oil Beetle, Melo6. 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 Meloes 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 Meloe is sometimes greater than that which I have al- 

 ready stated. On the 1st of May 1836 I captured a M. proscarabceus 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 lialf 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 

 the 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 



