PHYTOMYZIDAE ASTEIDAE BORBORIDAE PHORIDAE. 47 



FAM. LYIII. PHYTOMYZIDAE. 



Ckaract. Front bristly ; border of the mouth with vibrissse on each side. 

 Middle tibiae with spurs ; all the tibiae without erect bristle on the 

 exterior side. Wings without bristles on the costa ; first longitu- 

 dinal vein very short ; auxiliary vein connected with it at the tip ; 

 basal cells existing, but small ; posterior transverse vein wanting. 



The genus PHYTOMYZA is represented in N. A. 



FAM. LIX. ASTEIDAE. 



Charact. Front bristly above; border of the mouth with a vibrissa at 

 each side. Middle tibise with spurs ; all the tibiae without erect 

 bristle on the exterior side. Wings without bristles on the costa ; 

 first longitudinal vein exceedingly short ; auxiliary vein connected 

 with it only at the tip; second longitudinal vein very short; two 

 posterior basal cells as well as the posterior transverse vein want- 

 ing. 



No N. A. species of this small family is as yet known. 



FAM. LX. BORBORIDAE. 



Charact. Thorax, scutellum, and abdomen flat; front bristly; face exca- 

 vated, with a vibrissa on each side of the border of the mouth ; 

 clypeus developed; first joint of the posterior tarsi abbreviated. 

 Neuration of the wing incomplete, only a commencement of the 

 auxiliary vein being at best visible ; the hindmost two basal cells 

 are not complete in all genera. 



N. A. seems to possess numerous species of the genus BORBORUS, 

 which have not yet been carefully compared with the European 

 species. One species taken in Cuba is identical with an African 

 one. 



FAM. LXI. PHORIDAE. 



Charact. Antennae apparently single jointed, with a long bristle. Wings 

 with several stout veins running into the costa, and three or four 

 weak ones, which run across the surface of the wings and are not 

 completely connected with the hindmost of the stout veins, from 

 which they appear to issue. Femora flattened. 



Many species of PHORA seem to occur in N. A. ; their form, as 

 far as I am acquainted with them, differs in no way from that of 

 the European ones. 



