WASPS, SOLITARY AND SOCIAL 



gnats, all of them, except two, being dead. On one of 

 the dead ones was the egg, which had probably been 

 laid within a few hours. 



The egg hatched two days later, on July twelfth, but 

 on the fifteenth the larva died. By this time many of the 

 gnats looked very dry, although we had tried to arrange 

 for both moisture and ventilation by packing the bottom 

 of the tube with pith and covering the top with muslin. 



Further watching gave us one more wasp of this 

 species, in the same stump. This time the nest was only 

 two inches from the surface. It contained four dead 

 gnats and two live ones, but no egg, showing that the egg 

 is not always laid on the first ones stored. 



Much later in the season, toward the end of August, 

 we found another species of Rhopalum which proved to 

 be new, and for which Mr. Ashmead has proposed the 

 name rubrocinctum, since it wears a red girdle around 

 the front end of the abdomen, being otherwise dressed in 

 black like pedicillatum. It makes its home in the stalks 

 of raspberry bushes. We opened a stem which contained 

 thirteen compartments, separated by partitions of pith. 

 These were filled with black, gray, and green gnats, 

 which were packed in so closely that they were doubled 

 over and pressed out of shape. Each cell contained 

 from twentv-five to thirtv gnats. In some of them were 



J * O 



74 



