GENUS PSOKOPHORA 343 



Original description : — 



" $ — Hoary ov dark cinereous, with scanty frosty cinereous scales. 

 The first twelve joints of the antennae with the bases pale and 

 slender, and the apices thickened and piceous, all with not very 

 dense pale fuscous plumes ; the last two jomts fuscous ; eyes black ; 

 proboscis pale testaceous, with the base and apex dusky ; palpi 

 longer than the proboscis ; the two basal joints short and piceous, the 

 remaining two pale yellow, with scanty villosity ; the last wanting. 

 Legs pale yellow, with the joints indistinctly testaceous ; tibiae longer 

 than the first tarsal joint ; the anterior and middle tarsal claws are 

 wanting, but the hinder are long, the external over twice as long as the 

 inner one, with a very long additional tooth beneath ; wings hyaline, 

 shghtly yellow, the veins clothed sparsely with long slender fuscous 

 scales ; first sub-marginal cell twice as long as its stem, the second 

 posterior of the same length as its stem. Length. — 4*50 mm. 



" Habitat. — Navarro, in Argentina." 



Genus VIL PSOROPHORA, R. Desvoidy 



(" Essai," p. 412 ; " L. A." p. 38). 



The genus Psorophora was constituted by E. Desvoidy in 

 1827, and it is difficult to understand why the generic value of so 

 distinct a type should have been denied by all subsequent 

 entomologists, until the genus was revived by Arribalzaga in 

 1891. 



Though not so shaggy as Mucidus, it may be fairly said to 

 belong to what may be called the hirsute genera of Mosquitoes, 

 but the wings are not brindled in the same way as is the case in 

 that genus, and the scales of their veins are like those of Culex 

 and Stegomyia. 



Owing probably to the defective character of the lenses avail- 

 able at that date, Desvoidy was led to give as the leading 

 character of his new genus, the presence of peculiar scale-like 

 structures, which he thought he made out, overlying and protect- 

 ing the prothoracic stigmata. As a matter of fact, nothing of the 

 sort is to be found in these gnats, and the supposed operculum is 

 really nothing more than a tuft of scales covering the shoulder 

 callosities. 



In many respects they may be said to be intermediate between 

 Mucidus and Paiwplites, the legs and general appearance being 

 much as in the former, while the arrangement of the scales on 

 the head and thorax resembles that in the latter genus, though 

 there are some stiff linear scales just at the juncture of the nape 

 with the neck. The ? palpi too, though certainly proportionally 



