TEUCHOLABIS. 131 



with the inner end of the subrnarginal cell. The comparative 

 length of the cells in the apical half of the wing and the corre- 

 sponding shortness of the two basal cells, are among the striking 

 characters of this genus. The stoutness of the veins and the 

 clearness of the membrane of the wing are likewise characteristic. 



Teucholabis seems to be peculiar to the American continent, 

 at least no species belonging to it has as yet been discovered in 

 Europe. Besides the North American species described by me, 

 the following species, by former authors, belong here : — 



Limnobia simplex Wied. Auss. Zw. I, p. 549, from Brazil. I 

 have seen the original specimen in Mr. Loew's collection. 



Limnobia flavithorax Wied., from Brazil, according to Dr. 

 Schiner, who also describes a new species — T. spinigera {Reise, 

 etc. der Novara, Diptera, p. 44). 



Rhamphidia scapularis Macq. Dipt. Exot. I, 1, Tab. X, fig. 1 ; 

 likewise from Brazil, is, to all appearances, a Teucholabis. 



I have seen several specimens from Mexico in Mr. Bellardi's 

 collection. In drawing the generic character I had, besides T. 

 complexa, a male specimen from Mexico before me, which I owe 

 to the kindness of Mr. Bellardi. Its wings are somewhat nar- 

 rower than those of T. complexa. 



This genus, first established by me in 1859 (Proc. Acad. Nat. 

 Sci. Philad. p. 223), for the North American T. complexa, and 

 now corroborated by the comparison of several other species, is 

 very easily distinguishable by its neck-like collare, its broad, clear 

 wings, and the peculiarities of its venation. No immediate rela- 

 tionship can be pointed out. 



The name is derived from tsv%a, weapons, and a.a/3ts, forceps, 

 in allusion to the horny processes of the male forceps. 



Observation. Besides the South American and Mexican species 

 mentioned above, as belonging to Teucholabis, I have seen in Mr. 

 Bellardi's Mexican collection two forms, closely related to this 

 genus, but which may perhaps be separated from it. One of them 

 is distinguished by the presence of a supernumerary cross-vein 

 at the extremity of the second longitudinal vein, dividing the 

 marginal cell in two parts, and by the shortness of the first 

 posterior cell, in consequence of the subrnarginal cell being in 

 immediate contact with the discal cell. The 16-jointed antennae, 

 the development of the collare, the stoutness and pubescence of 

 the feet, the shortness of the first longitudinal vein and of the 



