3i8 Records of the Indian Museum. [Vol. IV, 



^ovi piumicornis, F. , pallida, F., and punctipennis , Say. (a 

 North American species), with others, are retained by Kertesz 

 under Corethra. This is obviously wrong, since Loew's principle 

 in establishing Mochlonyx was a sound one, i.e., " metatarsus 

 several times shorter than the next tarsal joint," as contrasted 

 with those species in which the metatarsus is longer than the 2nd 

 tarsal joint.' The separation of these groups is justified : Loew 

 lost his genus through unfortunately giving the name Mochlonyx to 

 that group of species containing the t3'pe species of Corethra, Mg. 

 Of course, in the days in which he wrote it was sometimes not 

 easy to distinguish which species was intended by an author as 

 the type of his genus '^ and this may have authorised him to split 

 off an}' group, or particular species at will. 



Corethra, Mg., must therefore always stand for culiciforiiiis, 

 with its congeners. 



Coquillett in 1903 erected Sayomyia for " Corethra puncti- 

 pennis" S^y., which he admitted as congeneric with plumicornis, 

 F. (the latter species possessing crystallina, De G., and others as 

 synonyms), both of which species have now to be placed in 

 Chaohorus. 



The synonym}' of the species immediately concerned will 

 stand thus : — 



Corethrinae [Subfamily of Culicidae.) 



Corethra, Mg., 1803. 



[Mochlonyx, Loew, 1844,) 



1. culiciformis, De Geer [Tipiila id.). Type of genus. 



2. velutina, Ruthe [Mochlonvx id..hoew ; type of Mochlonyx) 



[effoetus Wlk.). 



3. cinctipes, Coq. 



Chaoborus, lyichtenstein, 1800. 

 [Sayomyia, Coq., 1903=) 



1. plumicornis , F. [Tipula id.). Type of genus. 



2. punctipennis , Sa3^ (type of Sayomyia). 



3. All other species referred to Sayomyia since Theobald's ac- 



ceptance of the genus, but previously placed in Corethra. 



The three other genera recorded by Theobald appear to me 

 built on very weak characters and I should prefer to regard them 

 as subgenera of Chaohorus only. Each contains but one species. 

 They are Pelorempis (Joh.) americana, Joh., Corethrella (Coq.) 

 hrakeleyi, Coq., and Eucorethra (Underwood) underwoodi , Underw. 



E. Brunetti. 



i Theobald (Gen. Ins.) is distinctly wrong in terming the joint following the 

 metatarsus as the first, since the metatarsus itself is the \st tarsal joint, the suc- 

 ceeding joint being the second. 



* I have seen it stated somewhere that Meigen placed what he considered all 

 the most typical species in the middle of the genus, and those tending to aberration 

 at one end or the other of it. 



