342 ENTOMOLOGICAL NEWS [Oct., 'lO 



scarcely wider than the puparium and leading out toward the 

 upper end ; the aperture of exit softly drawn together. Length, 

 20-25 mm. ; width, 10-12 mm. 



Unfortunately, all galls collected showed that the insects had 

 but recently emerged. Obviously they were unknown Try- 

 petid galls of a large species which emerged in early Septem- 

 ber, and looking up the list of known life histories of the 

 local species, everything pointed toward Eurosta comma Wied. 



To verify this I had to wait one year, and was not disap- 

 pointed in finding them at the same place in August, 1907, and 

 ready to emerge. In the meantime I betook myself to Lucas- 

 ton, N. J., where I always collected E. comma in September. 

 After a little search I located the galls and was surprised to 

 find them on Solidago rugosa Mill., while those from Rich- 

 mond Hill, L. I., were taken on Solidago juncca Ait. 



A difference in the host-plant might mean a difference in the 

 species, hence the emerging of these flies was awaited with 

 considerable interest. Flies from both cages began to emerge 

 September 7 and continued until October 8. The flies reared 

 from Solidago juncca proved to be the true form of Eurosta 

 comma Wied. (see plate), but those from Solidago rugosa 

 taken at Richmond Hill, L. I., differed uniformly from this 

 species and proved to be a form new to science. 



Eurosta elsa n sp. 



Front sparingly beset with minute yellowish hair, the bristles are 

 brownish. The upper surface of thorax clay-yellowish pollinose with 

 short pile of same color. Scutellum brownish with two bristles. Abdo- 

 men reddish-brown with short blackish pile. Ovipositor conical, attenu- 

 ated near apex, dark brown with black pile, transversely with fine ridges. 

 Femora, middle and hind tibiae reddish-brown : front tibi?e and all 

 tarsi pale brownish yellow. Wings broad and rounded, dark brown 

 with a number of small semi-transparent dots scattered over the sur- 

 face. The extreme tip of wing with a narrow hyaline border and some 

 hyaline indication at the end of sixth vein. A small triangular hyaline 

 spot on the anterior margin beyond the stigma rarely exceeding the 

 second longitudinal vein. 



This species resembles E. comma Wied. very closely. It can 

 be readily distinguished, however, in both sexes by the trian- 



