PAKASITE, APHIDIUS TESTACEIPES. 



Ill 



Mr. Kelly, of this bureau, later took up the observations at this 

 point, during the fall of 1908, and published the results of his obser- 



Fig. 22. — Position of larva of Apludius testaceipes in the body of the spring grain-aphis at the beginning of 

 the change to a yellowish color. Much enlarged. (Original.) 



vations in the Proceedings of the Entomological Society of Wash- 

 ington. 1 Mr. Kelly confined some aphidids that were nearly dead 



from parasite attack on a slide and 

 observed them under the microscope. 

 He found that as the body of the "green 

 bug" takes on a brownish tint, the 

 Aphidius larva within makes a longi- 

 tudinal slit or opening in the ventrum 

 and enlarges it until it is more or less 

 oval in shape, as shown in figure 24. 



The rigid, firm manner in which Tox- 

 optera grasps the object upon which 

 it is resting at death apparently has the 

 effect of holding it in place while the 

 movements of the parasitic larva are 

 going on within. When the opening is 

 complete the larva begins to spin its cocoon, at the same time 

 ejecting a glutinous fluid that makes the strands adhere to any object 



Fig. 23. — Full-grown larva of Aphidius 

 testaceipes taken from body of the spring 

 grain-aphis as shown in figure 22. 

 Much enlarged. (Original.) 



i Proc. Ent. Soc. Wash., vol. 11, No. 2, pp. 64-66, 1909. 



