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ENTOMOLOGICAL NEWS. 405 
in the Wing Venation in some Tipulidae. 
R. W. Doane, Stanford University. © 
hd : (Plate XVIL) 
al In 1 all systematic work on the Diptera the wing venation is 
_ accharacter that is used perhaps more than any other in sep- 
, SIIIEGe aivens and in memy instances ie of coal et 
ty cg eer eoce i of ral 
Oa type. In the families with the more generalized type of 
however, there is more or less of a tendency to varia- 
EENtliy in the relativelength and position of some of the 
glee rg 
oat ae In the Tipulidae the presence or absence of the second pos- 
oc peetiseniea tar 
__ the discal call are characters that are largely used, The cell 
__ is always present in normal specimens of Tipula. I have be- 
fore me a pcinen of simplex Doane, in which this cell 
ta pet Pee Se Wine) ocearvins Se 
be i: tly normal (See Fig. 1; in all the figures only the out- 
Bs B of the wing and the venation is shown, as the marking 
i in some instances obscure the point that we wish to 
ow). The wings of the male of this species are subject toe 
ite variation in size and shape and intensity of the 
"markings, but the venation is, as a rule, quite constant. (Com- 
ee 
= One of the principal characters that is often used for separat- 
a ing the genus Tipula from Pachyrhina is the presence or ab- 
___ sence or short length of the petiole of the second posterior cell. 
In Pachyrhina this cell is sessile or with a very short petiole, 
j _ while in Tipula the petiole is usually longer. There is con- 
38 siderable variation in this respect in both genera, however, even 
___ within the species, and indeed sometimes in the two wings of 
the same individual as shown in figures 4 and 5, which are the 
fight and left wings of a specimen of Pachyrhina ferruginea, 
__ more or less variation is often shown. In the right wing, Fig. 
4, the second posterior cell has a very distinct and, for a 
Pachyrhina, rather long petiole. In the left wing, Fig. 5, this 
