SYRPHIDAE OF MAINE. 231 



first pair on the middle of the second segment, inner ends rounded ; the 

 others at the basal corners of the third and fourth segments, sub- 

 quadrate, a little longer on the median side extending broadly over 

 the margins. In the female the abdomen (Fig. 30-1^) is shorter and 

 oval, shining, with four pairs of orange spots the first pair small, iso- 

 lated, near the middle of the segment; the third and fourth pairs sub- 

 triangular, touching the anterior margins, the posterior point rounded, 

 the spots (either isolated or) narrowly reaching the side margins at 

 the extreme base of the segment; the fifth segment with a pair of small 

 slender basal spots. Legs variable, yellow to black. 



SPHAEROPHORIA CYLINDRICA Say. 



(See also 33, p. 538 and 35, p. 59). 



This is an exceedingly common, and one of the most valu- 

 able aphidophagous species about Orono, and probably through- 

 out North America. It has a variety of species of prey and 

 may be expected in almost any colony of aphids. 



Partly grown larvae were taken June 17 from among Aphis 

 viburnicola on Viburnum opulus; were full grown by June 28, 

 in puparium June 30 and emerged as adults July 7. Other 

 larvae collected from the same source June 25, pupated July 2 

 and emerged July 9. 



On July 7 four larvae and one pupa were collected on Rose 

 among Macrosiphum solanifolii, but all were parasitized. 



A small larva collected July 14 among Aphis rumicis on 

 Evonymus alatus was full grown and pupated July 24, emerging 

 July 30. On the same date larvae were collected from Myzus 

 cerasi on wild cherry and a pupa from Phorodon humuli on 

 plum. The former pupated July 17 and all emerged July 22. 



On July 1 6 a pair were taken in coitu about blossoming turnip 

 at 10 A. M. By 3 P. M. of the same day the female was ovi- 

 positing which continued until the death of the female on 

 July 19. By the latter date many of the eggs were hatching. 



July 26 two parasitized larvae were taken from Aphis 

 cerasifolii on Prunus virginiana and July 28 two puparia from 

 the same host, the flies emerging August 3 and 6. July 31 a 

 puparium was taken from flowering currant, the adult emerg- 

 ing August 7. And on the latter date larvae and pupae were 

 found in all stages of development on rape, sparingly infested 

 with Myzus persicae. Adults from these puparia emerged 

 August 14. 



