ART. 23. BLISTER BEETLE TEICRANIA PARKER AND BOVING. 11 



stages have not been found satisfactory, owing to failure in many 

 cases to discover the exact time of the second molt and to the neces- 

 sity of killing many of the larvae in different stages to provide ma- 

 terial for morphological study. Out of eight larvae that were per- 

 mitted to complete their larval development six had transformed to 

 the pupal stage by August 23, 1920. All six were taken from the 

 ground in cells of the host in the first stage on June 9, 1920. They 

 completed the fourth larval stage — that is, the period of feeding — on 

 dates ranging from July 4 to July 19. In other words the ap- 

 proximate time of feeding in these cases varied from 26 to 41 days 

 under laboratory conditions. On August 31, 1920, two cells of Gol- 

 letes were taken from the ground each containing the parasite; in 

 each case the beetle was in the pupal stage. Both of these beetles 

 as well as all those permitted to reach the pupal stage in the labora- 

 tory had transformed to the adult stage by September 17, 1920. 



In the development of the larva the skins of the first three instars 

 are cast off free of the insect, but the fourth cast skin is not rup- 

 tured at all, the larva simply shrinking away from its skin and 

 remaining within it. Likewise the fifth skin is not ruptured but is 

 cast off within the fourth in the same manner as the fourth is cast off. 

 The skin of the sixth instar, however, which immediately precedes 

 the pupal stage, is ruptured and pushed down to the posterior end 

 of the pupa where it may be found adhering to the ventral side of 

 the pupa within the fifth larval skin. Thus the fourth and fifth 

 larval skins serve as a protecting case for the pupa within which the 

 beetle finally transforms to the adult stage and from which it emerges 

 the following spring to begin anew the life cycle of the species. 



To Edward S. Reinhard we are indebted for the following inter- 

 esting observations on the life-history of this beetle. On April 24, 

 1921, he obtained from a burrow of Colletes inequalis Say near 

 Poughkeepsie, New York, a brood cell containing the larva of this 

 beetle that had completed its fourth stage and perhaps its fifth also. 

 At least the larva was lying free within the fourth cast skin. The 

 beetle was removed from the brood cell of the bee but was not other- 

 wise disturbed. On July 29, 1921, Mr. Reinhard found that this 

 larva had broken through the wall of its protective covering com- 

 posed of its cast fourth and fifth skins and was lying naked in the 

 breeding receptacle. On August 12 it transformed to the pupal 

 stage and on September 5 to the adult condition. 



From this data obtained by Mr. Reinhard it is evident that this 

 individual for some unknown cause failed to complete its transforma- 

 tions in the summer of 1920 and, consequently, passed the winter of 

 1920-21 in the larval condition and completed its transformations as 

 noted above. In our investigations no case of this kind was observ^ed. 



