154 MAINE AGRICULTURAL EXPERIMENT STATION. 1917. 



-ing European species of Platychirus in Maine : P. scutatus Meig. ; 

 P. immarginatus Zett. ; P. discimanus Loew (Dr. Edith M. Patch, 

 collector) ; and P. angustatus Zett. 



It is of particular interest to record species of the two gen- 

 era Platychirus and Xanthogramma as aphidophagus since they 

 have each been recorded as having species which are scavengers 

 in the larval stage. These two genera should be added to the list 

 of ten genera given in the author's previous bulletin as aphido- 

 phagous, at least in part. 



The Aphididae named in this bulletin have all been deter- 

 mined by Dr. Edith M. Patch, Entomologist. The writer is also 

 indebted to Messrs. W. F. Pride, Geo. B. Newman and Robert 

 K. Fletcher for assistance in collecting and caring for material. 



XANTHOGRAMMA DIVISA Williston. 



This is an aphidophagous species occurring sparsely in the 

 larval stage among aphids on a number of our shade and forest 

 trees, and occasionally increasing to abundance when a favor- 

 able infestation of aphids is available. 



It is the handsomest larva of Syrphidae that I have seen 

 and all stages present interesting structural characteristics. 



Verrall 1 says of the genus : "Not much is known about the 

 metamorphoses, but the larva has been reared from heaps of 

 turf," so that the members of the genus have been believed to be 

 scavengers. However, a report of the Hawaiian Sugar Planter's 

 Experiment Station gives a photograph of the adult of a species 

 of Xanthogramma among the predaceous insects of the island. 



The records of the immature stages are as follows : 



A well-grown brown larva collected by Mr. W. F. Pride, 

 July 6, 1915, among Aphis cerasifoliae Fitch on choke cherry 

 (Primus virginiana), succumbed in the laboratory after a long- 

 drawn-out period of slow starvation, during which it failed to 

 pupate. 



A very small larva collected on Cornus sp. (Aphis corni- 

 foliae Fitch), July 12, 1915 was ashy-gray in color instead of 

 brownish. It was fed in confinement from Aphis cornifoliae and 

 in about a week had attained full size and become a beautiful 

 tan in color. It was fed every other day until July 31, when it 



'Verrall, G. H., British Flies, Vol. VIII, Syrphidae, p. 448. 



