240 LECTURE XVIIl. 



insect of the wasp tribe {Polistes tnajor), showing the larvae and their 

 cells in every stage of growth : the smallest larvae and the shallowest 

 cells are at the lower margins of the pendent nest ; and observe how, 

 in these beginnings of cells, the part of the incomplete circumference 

 forms two, three or more sides of a complete hexagon, demon- 

 strating that this is the form of cell originally and expressly made 

 by the insect, and not the accidental and inevitable result of the 

 reciprocal pressure of originally cylindrical cells, moulded upon the 

 bodies of their simultaneously -working fabricators. The parent wasp 

 of this colony began her labours in spring. A solitary mother and 

 independent builder of the required shelter for her offspring, she 

 herself nursed and fed her first brood, which, being non-breeding 

 labourers, soon aided their parent in building the cells and rearing 

 her larvae. You will observe that the full-grown grubs are shut in 

 by a transparent convex pellicle, which covers the mouth of the 

 cell. 



In the common wasp, the larva is hatched eight days after oviposi- 

 tion ; it grows to its full size in twelve to fourteen days, then spins 

 its delicate hood, casts its integument, which has grown with its 

 growth from the time of quitting the e^g, and, after a passive pupa 

 state of ten days, emerges a perfect insect. The males and perfect 

 females are reared at the beginning of autumn : the abundance of food 

 yielded by the ripe fruit at that season may influence the higher de- 

 velopment of the larvae, which are fed by the regurgitated contents of 

 the crop of the nursers. 



The fertile females share with the non-breeders or neuters of the 

 rapidly increasing community, the labour of rearing the young broods : 

 the males, or drones, perform no kind of work. At the close of 

 autumn, when provender is scanty, and hardly to be got, the neuters, 

 by a strange, and, as it would seem, perverted instinct, save the later 

 brood of grubs from the pangs of famine by killing and casting them 

 out of the nest. The young females are impregnated previous to the 

 setting in of winter : the males soon after die ; the females then dis- 

 perse, seeking winter quarters in sheltered situations ; and those 

 which survive the rigours of the frosty season commence, at the re- 

 turn of spring, the foundation of a new colony. 



The higher instincts of the honey-bee (Apis onellifica) teach it to 

 lay up a winter store of food, upon which, the males having been 

 destroyed on the performance of their sole office, the queens, with a 

 family of neuters, subsist till spring. The neuters alone now re- 

 commence their labours of housing, in waxen cells, the eggs of the 

 fertile female, and feeding the larvae. New colonies so raised suc- 

 cessively emigrate from the parent hive, or swarm ; they consist of a 



