NOTES ON THE BEHAVIOR OF A PARASITIC BEE OF 



THE FAMILY STELIDAE 



C. H. TURNER 



Sumner High School, St. Louis, Mo. 



So far as my knowledge goes, nothing has been pubHshed 

 upon either the habits or the behavior of the American Stelidae ; 

 therefore, it is thought that the following notes, although frag- 

 mentary, will prove of interest to students of animal behavior. 



In the early part of May, 191 1, I received, from Mr. Phil Rau 

 of St. Louis, a few mud cells containing thirteen imago bees of 

 the family Stelidae, about a third of which were females. The 

 cells in which these bees were found were those of one of the 

 mason wasps {Pelopaeus sp. ?). That these bees spent their 

 pupal life in those cells is a certainty, for they emerged from 

 their pupal cases while in the possession of Mr. Rau. Since 

 the food of bees is so unlike that of wasps, it does not seem prob- 

 able that these bees are parasites of the mason wasp; therefore, 

 it seems safe to presume that this mud-dauber's nests had been 

 appropriated by some non-parasitic species of solitary bee, 

 and that a female bee of the family Stelidae came along and, by 

 depositing her eggs upon the food intended for the young of 

 her host, initiated a tragedy. 



As soon as received by me, the mud cells containing the bees 

 were placed on the floor of an insect cage sixteen inches high, 

 twelve inches wide and twelve inches deep. The bottom and 

 framework of this cage were constructed of wood, the sides 

 and top were covered with fine wire gauze. When not under 

 observation, the cage containing the bees was kept in an ordinary 

 school-room, with an average temperature of 70 degrees by 

 day and a minimum of 60 degrees by night. On nights when 

 there was danger of the temperature falling below sixty, the 

 cage was placed in a conservatory, where the terriperature was 

 between 70 and 80 degrees. 



These mud cells from which the insects were hatched were 

 to them a real home. At night or whenever the room was 

 darkened or when the atmosphere became a little cool, these 

 bees would retire to the mud cells and rest therein. The method 



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