128 



THE SPRING GRAIX-APHIS OR i c GREEN BUG. ' ' 



neura amen can a. He also reared it from Ifacrosiphwn viticola and 

 Chaitophorus sp. Pachyneuron sp. appears to be quite generally dis- 

 tributed but little or nothing is known of its life history. 



Allotria sp. 



AUotria sp. (fig. 37) is recorded as a secondary parasite. Mr. 

 Parks verified this by careful rearings at Wellington, Kans., in 

 1909, for he was able to rear it only from parasitized aphidids. The 

 junior author and Messrs. Kelly and Urbahns have observed it 

 ovipositing in parasitized dead aphidids also. Mr. Parks found in 

 his experiments that it developed from egg to adult in about 21 



days, under favor- 

 able temperatures. 

 We have reared 

 it only in conjunc- 

 tion with Aphidius. 

 Messrs. Kellv and 

 Urbahns reared it 

 from Aphis gossypii 

 and A. brassicse at 

 Wellington, Kans. ; 

 Mr. Parks reared it 

 from Toxoptera 

 from the same local- 

 ity; Messrs. Parks 

 and Kellv also 

 reared it from Tox- 



Fig. 37.— Allotriasv., a secondary parasite of the spring grain-aphis, ilale. optera at Washhlg- 

 with female antenna at upper right. Greatly enlarged. (Original.) + "r\ p A|\_ p 



N. Ainslie reared it from Aphis avense and Hyalopterus dactylidisirom 

 the same locality. Mr. Kelly reared it from Macrosiphum viticola 

 from Wellington, Kans., and the junior author reared it from Myzus 

 persicse at Lafayette, Ind. 



PREDACEOTJS ENEMIES. 

 Lady-beetles. 



Probably next in importance to the genus Aphidius come the 

 ladybird beetles. These beetles, in both the adult and larval stages, 

 feed upon plant-lice. In 1907 they became very abundant, destroy- 

 ing countless numbers of Toxoptera and greatly assisted Aphidius in 

 subduing the pest. Plate VIII represents the manner in which the 

 pupa3 are found attached to plants in fields badly infested with 

 Toxoptera; to the left is a 2-inch section of an old cowpea stem; to 

 the right, two short sections of wheat stems. Oftentimes as many 

 as 30 or more pupas could be found within the space of a foot of a 

 single drill row. Adults deposit eggs upon any convenient object, 



