TWO sp]e;cies o^ macrosiphum. 89 



(1) Aug. 12. A lot of 30 alate individuals transferred 

 from peas to shepherd's purse. Aug. 25. The progeny of the 

 foregoing are small and yellowish but a healthy, vigorous 

 colony. 



Prom Peas to Various Plants. 



On Barley. 

 (m) — (x). Tv>^elve tests were made attempting to transfer 

 M. destructor from peas to barley (Hordeum vulgare L.)- 

 The barley was 6 inches high at time of tests and- growing well. 

 The aphides deserted the barley and crawled to the sides of the 

 cage where they died within a few days. 



On Wheat. 



Four tests were made attempting to establish colonies on 

 wheat. Two lots of 10 apterous adults were transferred from 

 sweet peas to wheat July 27. July 31 these and their progeny 

 were dead. One lot of 10 alate aphides was placed on wheat 

 July 2y and by July 31 these had died. August 10 several hun- 

 dred specimens were taken from peas and transferred to wheat. 

 August II scarcely any aphides could be seen on the plants. 

 August 15, aphides all dead. Wheat was 6 inches tall at time 

 of test and growing well. 



On Oats. 



July 27, a lot of 10 apterous adults transferred from peas 

 to oats. July 31, aphides all dead. 



On Purslane. 



July 17, a lot of 15 apterous adults transferred from peas to 

 common purslane (Portulaca oleracea 1^.). July 21, adults all 

 dead. No young to be found. 



Oti Beets. 

 August 10, a lot of 15 alate individuals which had migrated 

 from peas to cloth on the cage were transferred to beets in 

 small cage. These did not remain on the beet plants but flew 

 to sides of cage where they died before August 15. 



