366 ERNEST A. BACK. 



by the wing. However, I believe that Loew's type pair of 

 bilineata are more an exception than the rule in regard to the 

 color of the thoracic stripes. I have before me over twenty 

 specimens from Florida which are undoubtedly bilineata, a 

 few of them are as Loew says, but the greater part are at once 

 separated by the velvety black stripes. I am aware that 

 these are apt to be variable as to intensity of color, but the 

 velvety black stripes are the rule in bilineata, while in sym- 

 macha they are not. 



In considering the wing, I will here give a translation of 

 Loew's description: — This species is with difficulty distin- 

 guished from bilineata unless it is smaller, and has less broad 

 wings, otherwise colored with cinereous. This color in bilin- 

 eata fills the entire submarginal cell of the wings and the first 

 posterior cell, thence wholly covers the wing from the margin 

 as far as the base of the second submarginal cell and the 

 second and third posterior cells excepting the very base. In 

 this species (symmacha) the cinereous color does not reach the 

 posterior margin in the second submarginal cell, nor indeed 

 both margins in the first and second posterior cells, excepting 

 near the margin of the wing; in the third posterior cell, indeed, 

 it is separated from all the margins by a hyaline border; in 

 bilineata in the fourth posterior cell the cuneate spot is seen 

 subcoherent with the apical margin; in symmacha the oblong 

 border is separated everywhere alike from all the margins by 

 the hyaline border; in the former, the large triangular spot 

 in the fifth posterior cell is observed coherent with the margin 

 of the wing, in the latter, the triangular spot of this cell is 

 separated from the margin of the wing by a hyaline border; 

 the axillary angle of bilineata shows no (or slight) trace of a 

 cinereous picture, that of symmacha shows a border parallel 

 with the margin of the wing. The third posterior cell of 

 symmacha, on account of the more narrow wing, is less broad 

 than that of bilineata. 



Deromyia ternata. 



Diogmites ternata Loew, Cent., VII, 38, 1866. 

 % 9 • — Length 19-22 mm. — Wholly reddish-yellow, except the three 

 velvety black stripes of the thoracic dorsum. Abdomen cylindrical, 



