THE CRANE-FLIES oF New YorK— Part [| 863 
most Limnophilini (Plates XXXVIII-XLI), or it may tend to retreat 
proximad toward the base of the wing as in many Eriopterini (Plates 
XXXIV-XXXVII), or it may be very far removed from the tip so that 
it lies before the base of the sector (as in the tribe Pekiciini, Plates 
XLI, XLII, and in the genus Ula, Plate XLI, 164). In some Anto- 
chini it is apparently lost by atrophy. In the subfamily Tipulinae only 
the more generalized species retain Sc; (Plate XLIII, 188 and 189), but 
Sc is present and is bent strongly into A; at its tip, thus forming a good 
subfamily character. 
The radius (R, fig. 128, a) is the strongest vein of the wing, and, with 
its sector, one of the most plastic. A, runs straight to the wing margin, 
but usually at about midlength of the wing it forks, sending off the radial 
sector (Rs). This is primitively twice forked, being forked and the 
branches forked again, dichotomously. These branches of the sector are 
numbered from 2 to 5, the upper fork carrying with it R. and R3 and the 
lower fork carrying with it Rs and R;. The full complement of branches 
of the radial sector is found only in the Tanyderidae (Plate XXX, 1). In 
the Ptychopteridae (Plate XXX, 2-4) the upper fork, Re+3, is fused to 
the margin; in the Tipulidae (Plates XXX-—XLVIID) it is almost always 
the lower of the dichotomous forkings, R4+5;, that is fused to the 
margin. 
The various ways in which the full complement of veins has been lost, 
by the fusing together of adjacent veins or else by the atrophy or dropping 
out of one or more of the branches, may be here discussed. In the 
Cylindrotominae (Plate XXX, 5-8) the appearance suggests the fusion 
of the upper fork of the sector (R2+ 3) with Ri, forming a long, backward 
fusion of Ri+2+3 from the wing margin. As suggested by the author 
in an earlier paper (Alexander, 1914 b:604—605) and later proved by the 
discovery of the Oriental genus Stibadocera Enderlein (Alexander, 1915 ¢: 
178-179), the loss of these veins is by atrophy rather than by fusion, 
and the vein that simulates Ri +243 is, in reality, Rs; alone and corresponds 
exactly to this vein in other tribes of crane-flies. In the subgenus 
Leiponeura of the genus Gonomyia (Plate XXXVI, 86-88), the vein 
R2+3 is fused to the wing margin, or, possibly, R; is atrophied after the 
fusion has proceeded almost to the margin. In the more generalized 
species of Gonomyia (Plate XXXVI, 89 and 90), the fork of Rz+3 is 
