BULLETIN 276, U. S. DEPARTMENT OF AGRICULTURE. 



sweetish taste because of the honeydew covering it, is rather relished 

 by cattle. Mr. Lawson Caesar (1911) reports that feeding cattle 

 with infested vines was supposed by one farmer to be the cause of 

 the death of some of his cattle, but there seems to be no proof and the 

 conclusions were probably incorrect. 



DISTRIBUTION AND ORIGIN. 



As will be seen on the accompanying map (fig. 1), this aphidid is 

 generally distributed over the United States and southern Canada, 

 especially in the eastern half, where it is more or less destructive 

 every year. It is likewise generally distributed throughout Europe. 

 Theobald (12) reports this species from Natal, South Africa, and Dr. 

 B. Das (in litt.) has found it plentiful in British India. 



Fig. 1. — Map showing the known distribution of the pea aphis ( Macrosiplium pisi) in America. (Original.) 



As an injurious species it occurred first in America along the At- 

 lantic coast. The following year (1900) it was very destructive in 

 Wisconsin and Michigan, and has since worked its way westward 

 to the Pacific coast. Recently Mr. F. C. Bishopp has sent in speci- 

 mens from Texas, where it seems to have gained a strong foothold. 1 



The fact that M. pisi was first observed in this country within 

 comparatively recent years and was first apparent in destructive 



1 Mr. BLshopp has kindly given the writer permission 1o quote his letter accompanying the specimens, 

 under date of Aug. 4, 1914, which reads as follows: 



The pea aphis was observed to be doing damage to English peas (garden peas) in experimental plats just 

 east of Dallas, shortly after the middle of May (HU4). The peas began blooming about April :in. On 

 May .' i the growth of the pen wa-i practically stopped and many vines turned yellow on account of (he 

 exceedingly heavy infedati m of aphides. On M iy 31 practically all of the pea vine-; were dead without 

 having produced a single pod. During the first three wee cs of June, lady beetles, principally Hippndamia 

 converqens, were ohserved to be destroying the aphides in greal numbers, and a few of tne pea \ ines were 

 almost cle ire: I of the " lire" and -darted to grow a lit t le: ho a e\ er , t lie\ never made any fruit. 



Mr. Bishopp further stated that the sweet peas and garden peas throughout the city of Dallas were prac- 

 tically destroyed. 



