NEW WORKS ON ENTOMOLOGY. 141 



bescence of a sombre colour, whereas the parasite is a gaily coloured 

 insect, destitute of pubescence, and readily observed from the bright- 

 ness of its colouring Much further investigation is 



still necessary before we can arrive at a knowledge of the real nature 

 of the connexion which exists between the bees and their parasites. 

 It has been supposed that the parasitic larva is hatched sooner than 

 that of the rightful owner of the nest, and that it consequently con- 

 sumes the food and leaves the larva of the bee to perish. But to this 

 I do not assent ; it appears so contrary to all natural laws that I can- 

 not think it even probable; nature I have never observed to be thus 

 wasteful of animal life — such a proceeding is unnecessary and there- 

 fore unlikely. Where a destruction of animal life is observed, it can 

 usually be traced to some reasonable cause, as the destruction of 

 the larvae of certain Lepidopt.era, being a check upon their super- 

 abundance ; a parallel to this does not appear to me to exist in 

 the case of the bees. I am more inclined to believe, that when 

 the parasite has deposited her egg upon the store of pollen, the 

 industrious bee at once deserts it and proceeds to construct a fresh 

 burrow ; and that the parasites which may be observed constantly 

 entering different burrows, do so in order that they may find the re- 

 quisite quantity of food, which will usually be much less than that 

 required for the industrious bee ; having found w r bich, they deposit 

 their egg, and the nest is then possibly deserted by its legitimate 



owner." 



"If 1 were asked which genus of bees would afford the most abund- 

 ant materials for an essay on the diversity of instinct, I should with- 

 out hesitation point out the genus Osmia." . . . "O.aurulenta 

 and O. bicolor are bees which commonly burrow in banks; the 

 latter being very abundant in some situations, forming colonies, but 

 although it appears to be the natural habit of these species to con- 

 struct tunnels in hard banks, with great labour and untiring per- 

 severance, still we find them at times exhibiting an amount of 

 sagacity and a degree of knowledge that at once dispels the idea 

 of their actions being the result of a mere blind instinct, impelling 

 them in one undeviating course. A moment's consideration will 

 suffice to call to mind many tunnels and tubes ready-formed, which 

 would appear to be admirably adapted for the purposes of the bees ; 

 for instance, the straws of a thatch and many reeds ; and what 

 could be more admirably adapted to their requirements than the 

 tubes of many shells? So thinks the bee ! O. aurulenta and O. 

 bicolor both select the shells of Helix hortensis and //. nemoralis ; 

 the shells of these snails are of course very abundant, and lie half 

 hidden beneath grass, mosses and plants ; the bees finding them in 

 such situation- dispense with their accustomed labour and take pos- 

 session of the deserted shells. The number of cells varies according 

 to the length of the whorl of the shell selected, the usual number 



