January, 1878] 1G9 



ON THE LIFE-HISTOEY OF SOME BLISTEE BEETLES. 



BY PROP. C. V. EILET. 

 {Extracted from tJie Transactions of the Academy of Science of St. Louis, vol. iii). 



It is generally stated by writers on the Hive-bee that the Oil- 

 beetle (MeJoe) is one o£ its parasites. The possibility that our more 

 common blister-beetles were similarly parasitic on bees, taken in 

 connection with the frequent complaints from apiarians of the whole- 

 sale death of bees from causes little understood, led me, some years since, 

 to pay attention to the biological characteristics of the blister-beetles, 

 in the hope of ascertaining whether or not they really bear any 

 connection with bee mortality. Erom these investigations I am 

 satisfied that Jleloe is only parasitic on the perfect Hive-bee as it is 

 on so many other winged insects that frequent flowers ; and that it 

 cannot well, in the nature of the case, breed in the cells of any social 

 bee whose young are fed by nurses in open cells. 



I have had no difficulty in getting the eggs or the first larvae of 

 several of our Vesicants, and described some of them at the Hartford 

 (1871) Meeting of the Am. Ass. Adv. Sc. ; but these young larvse 

 refused to climb on to plants furnished to them, or to fasten to bees 

 or other hairy insects. Nor would they nourish upon honey, bee- 

 bread, or bee larvae on which they were placed. They showed a 

 proclivity for burrowing in the ground, and acted quite diffei'ently 

 from those of Meloe or Sitaris, which not only readily attach to bees 

 in confinement, but which, in the case of Meloe, I have known to so 

 crowd upon mature Hive-bees as to worry them to death and cai;se 

 extended loss in the apiary. Explorations into the nests of solitaiy 

 bees gave no clue, and, in fact, the immense numbers in which the 

 more common blister-beetles occur rendered a parasitic life upon such 

 bees highly improbable. In sweeping plants and flowers with the net, 

 I had never met with any of the first larva) with w^hich I had become 

 familiar, as already indicated ; while I had on several occasions, in 

 digging ground where there was no trace of bee nests, met with the 

 curious pseudo-pupa so characteristic of the Family. "While analogy 

 and the law of unity of habit in species of the same family pointed, 

 therefore, to a parasitic life, I began to conclude, from the facts just 

 stated, that the parasitism was of another kind, having satisfied myself 

 by various experiments that the triungulins did not feed on roots. 

 Eew discoveries are stumbled upon. AV^e find, as a rule, that only which 

 we anticipate or look for. Late last fall, in digging up the eggs of 

 the Rocky Mountain Locust {Caloplenus spreitis) at Manhattan, Kansas, 



