WILLIAM G. DIETZ 107 



5. The basal deflection of Cu and the cross vein M-Cu, at 

 or before the fork of M, first mentioned by Czizek^- and hkewise 

 by Brunetti,*^ is somewhat variable and, according to Alexander," 

 approached by certain species of Tipula. I here wish to note an 

 instance of its variability. In a series of thirteen specimens of 

 P. (Tipula) pachyrhiiioides Alexander, the basal deflection of 

 Cu and the cross vein M-Cu occurs in three specimens before the 

 fork of M, in nine specimens at, and in one specimen after, the 

 fork of IM. 



Having thus summarized the characters, more or less constant, 

 as distinctive, I have in the present essay included all species 

 under Pachyrhina in which the antennae of the male possess 

 less than nineteen joints in the male, having the proboscis short 

 and stout and in which we find the afore-described hypopygial 

 characters. 



The habitus of the species with few exceptions is characteristic 

 and needs no further consideration. The species of Pachyrhina 

 relegated by Alexander^-" to Tipula, are here retained under 

 Pachyrhina, except califoimica Doane. This species with its 

 long proboscis, more elongated first antennal joint, and above all 

 the large ninth tergite with greatly extended lateral angles, makes 

 its relegation to Tipula, notwithstanding its strong pachyr- 

 hinoid appearance, a necessity. The specific name being preoc- 

 cupied, I propose xanthomela in its stead. 



In numerous species, at least some of the wing veins are setu- 

 lose, the setules arranged in regular rows and approximately 

 equidistant from each other. This character is also observed in 

 many Tipulas as well as other Tii)uli(lae. The setules are 

 easily removed by friction, but their presence is always indicated 

 by the setigerous punctures. This setulosity is most frequently 

 present on the costal veins, veins R, R^'*"'*- and veins ]\ii-='"''3 

 The radial sector and the veins limiting cell 1st M- are almost in- 

 variably free, likewise veins Cu and A^ "''"''". The veins are en- 

 tirely glabrous — free from setules — in P. oslari (except R) and 



'=0p. cit., ii, p. .50, (1911). 

 '^^Op. cit.,p. 340, (1912). 

 '^Op. cit.,p. 46G. 

 "Op. cit., p. 466. 



TRANS. AM. ENT. SOC, XLIV. 



