PARASITISM OF THE HYMENOPTERA. 157 



the developement of the parasitic larva is less rapid than 

 that of its intended victim, and this, by acquiring 

 early sufficient strength, neutralises the object of the 

 parents, and turns " the tables " upon its progeny. A 

 subdivision of this parasitical mode of breeding we 

 observe among the bees, which more resemble that of 

 the cuckoo than either of the other; and from this 

 circumstance, those genera of bees wherein it occurs 

 have been called cuckoo bees. Here it is merely the 

 food that is laid up in store, that has been preyed upon 

 by the larva of the parasite; for the bee not being at all 

 carnivorous, the genuine inhabitant for whom the provi- 

 sion was made is starved by its abstraction by this intruder. 

 In the bees that possess this habit, it is always an entire 

 genus, and not a portion of a genus, as we have ob- 

 served among the Sphecides ; although the same object 

 of resemblance is frequently obtained, by these parasitic 

 bees belonging very generally, from structural character, 

 to a cognate division of the group, as we shall have oc- 

 casion to instance below. With regard to structure, we 

 may here remark, that it occurs in a less fully developed 

 state throughout this second division of parasites ; but 

 this is compensated by the superior instinct with which 

 they are endowed, to enable them to evade the sagacity 

 of the insects upon which they prey. Instances, how- 

 ever, of fearful retribution we shall record below, when 

 we treat specially of the groups; and where we shall 

 show that severe punishment has followed the heedless 

 temerity of the parasite, when it has too rashly exposed 

 itself to the indignation of the enraged parent. Al- 

 though we have already observed that there are apparent 

 deficiencies in the analogical structure of these latter 

 parasites, we are not to note these as defects, but as a 

 further exemplification of the universal economy exhi- 

 bited every where in nature, which, fitting every thing to 

 its end, is never lavish in superfluous, and consequently 

 useless, implements. 



(143.) In speaking here of the parasitic habits of 

 the Hymenoptera, we may notice, that they are them- 



