June, 1901.] Smith : On Some Digger Bees. 65 



insect simply rolls itself in the flower that the pollen may adhere to 

 the mesh of interlacing branches of hair. This habit would seem to 

 make it an effective pollenizer for fruits ; but unfortunately no obser- 

 vations were made as to the kinds of flowers visited : therefore, I am 

 unable to say at present whether the insect is of economic importance 

 or not. I do know that the contrast between the yellow pollen and 

 the metallic color of the insect is very striking and identifies the stor- 

 ing specimen at a glance. 



June 30th, I made seven casts in bee mine No. 2, of which two 

 were accidentally spoiled. All of these were made close to the point 

 where the digging was done on the previous visit, and all were taken 

 out the same day. In addition, I also took out a number of larvae, 

 pupje, pollen cakes and eggs from the pit next to where the casts were 

 made. The main object of this digging was to obtain specimens ; 

 but incidentally it was noted that always, in the upper cluster, there 

 were two or three well-developed larvae, while in the lower clusters 

 either very young larva; or eggs only were found. In other words, 

 the bees, while they first complete the upper cluster before starting the 

 lower series of cells, do not fill more than three of the upper, before 

 they start on the lower series. The greatest number of filled cells 

 found in any one cluster was five, and in that case three of the lower 

 cells were also stocked. 



In cast I, I had three clusters and two branches which seemed to 

 represent random digging. In the upper series I found one pupa and 

 three full-grown larvae. Neither of the lower series contained any 

 larvse, but the filling of some of the cells had been begun. 



Cast 2 contained only an imperfect cluster and, as there was no 

 bee in the cast, it is probable that the owner met with an accident. 



Cast 3 had one partly completed cluster and one just started ; but 

 here the bee was in the cast, imbedded in one of the cells, none of 

 which were filled. This would seem to represent a very late start or 

 some accident that prevented work for a time. 



Cast 4, extended more than four feet down. Four clusters were in 

 whole or in part completed and three of them contained cells, either 

 filled or in progress of being filled. All stages from the pollen cake 

 without an egg, to the pupa were represented in this cast, but none of 

 the outside cells had material of any kind. It was the study of this 

 series that made the relation of the outer or air cells to the inner, 

 brood cells, entirely clear. The bee in this instance was in the cast. 



