Vol. V. June, ipoj. No. i 



BIOLOGICAL BULLETIN. 



GUESTS AND PARASITES OF THE BURROWING 



BEE HALICTUS. 



AXEL LEONARD MELANDER AND CHARLES THOMAS BRUES. 



During the months of summer every roadside presents a field 

 of busy insect-activity, as varied and interesting as it is unseen 

 and unheeded. Those insects, however, that we do notice are 

 seen during their idling moments and hence we are generally ac- 

 customed to stigmatize all as idlers with no aim beyond song or 

 frolic. But insects have a busy life --another phase of their 

 existence which many of us overlook. If we inspect some road- 

 side more attentively we shall be surprised to see many of the 

 self-same idlers working with diligence. Spurred by parental 

 anxiety these insects excavate their nests and store them with 

 food, doing for their young what their parents have done for 

 them. 



Out of this multiplicity of insect-life we shall select as an 

 example one of the burrowing bees of the genus Halictus, and 

 endeavor to tell what may be seen on any summer day. Halictns 

 (Chloralictus] pruinosns Robertson is a brilliant greenish bee, 

 measuring about one third of an inch in length, which lives over 

 an extended range, occurring from New Mexico, through Illinois, 

 to Massachusetts. It is the commonest Halictine at Woods 

 Hole, in the last-mentioned state, where the following observa- 

 tions were made. During the early part of summer these bees 

 commence their excavations along the roadsides wherever a 

 sandy slope presents a favorable situation, ami continue their 

 activities until early autumn, the colonies increasing in size, and 

 becoming more closely settled as the season advances. They 

 seem to be in the height of their vigor during the early part of 

 September in this region. Although their social instincts are 

 not so highly developed as those of Apis or Bombns, these bees 



