8 4 



WASP STUDIES AFIELD 



Trachelas tranquilla Hentz, which was much heavier than 

 herself. The spider's legs had been bitten off at the junction 

 of the coxae and trochanters. She dragged it with its 



FIG. 16. The twin-celled nests of Pseudagenia architecta, showing 

 the holes made by the emerging wasp. Exact size. 



smooth, rounded back downward, to prevent friction, and 

 grasped it with jaws near the tip of the ventral surface of 

 the abdomen. 



Ashmead, 13 in citing Walsh and Riley, says that the thim- 

 ble-shaped cells occur under bark, logs or rocks, and are 

 parasitized by Pteromalus sp. and Osprynochotus jun- 

 ceus Cr. 



Pseudagenia pulchripennis Cress. [S. A. Rohwer]. 



This medium-sized black wasp was found walking along 

 a path at Creve Coeur Lake on October 7, carrying a spider, 

 Phidippns andax Hentz [C. R. Shoemaker]. The wasp 

 was holding the spider by one of its chelicerae and walking 

 sidewise, the combination of spider and wasp forming a 

 right angle (see fig. 17). It moved in a very strange man- 

 ner, walking sidewise. This was the first wasp we had 

 ever seen travelling thus. Night was approaching and train- 

 time was drawing near, so we were obliged to abandon 



13 Psyche 7: 66. 1896. 



