868 CHARLES PauL ALEXANDER 
from it. This probably represents the first anal vein in these species, 
in which ease all three anal veins would be accounted for. 
The cross-veins.— The usual cross-veins of the wing have been indicated, 
for the most part, in the foregoing discussion of the longitudinal veins. 
The humeral cross-vein (h) is almost always present and forms a strong 
union between C and Sc near the wing base; it is of little systematic impor- 
tance. The radial cross-vein (vr) lies entirely in the radial field, and con- 
nects R, with either Rz or Ry +3, or it may lie exactly at the fork of the 
last-named vein. The radial-medial (r-m) cross-vein connects either 
Ri+5 with M,+. as in most crane-flies, or R; with M,+.2 as in Molophilus 
(Plate XXXIV, 65-70), or Rs with Mi+.2 as in Tricyphona kuwanai of 
Japan and in the genus Rhampholimnobia discussed above. The medial 
cross-vein (m) lies entirely in the medial field and connects either M, or 
Mi+2 with M;+,. The medial-cubital cross-vein (m-cw) connects either 
M or M; +44 with Cu. The arculus (ar) is a strong cross-vein connect- 
ing M with Cu at the base of the wing. 
Supernumerary cross-veins and spurs are frequently found in ecrane-flies 
and furnish convenient characters for defining genera, subgenera, and 
species. In Tanypremna regina, of the Colombian Andes, there is an 
abundance of cross-veins and spurs in the basal cells of the wings; in the 
related species Tanypremna columbiana there is a single strong cross-vein 
in cell MW. ‘These supernumerary cross-veins are very constant in their 
occurrence and position, and may be found in almost any cell of the wing. 
Needham (1908:220) drew a primitive crane-fly wing and indicated 
on it all the supernumerary cross-veins that are known to occur in the 
group, and the composite resulting was remarkably lke the wing of a 
neuropteroid scorpion fly, thus providing additional confirmation for 
the belief that the Panorpidae or some closely allied group gave rise to 
the dipterous line of evolution. Epiphragma (Plate XLI, 158) has the 
cross-vein in cell C; Geranomyia (Plate XXXI, 10-13) and many 
Rhipidia in cell Sc; Helobia (Plate XX XVII, 98) and Dicranophragma 
(Plate XX XIX, 139) in cell R,; Ephelia (Plate XX XIX, 137 and 138) 
and Idioptera (Plate XXXVIII, 115) in cell M; Dicranota (Plate XLI, 
167-169) in cell Ri, alongside of the r cross-vein; Discobola (Plate XX XII, 
41) in the first anal cell, forming a strong union between the two anal 
veins; and so on in great variety. Strong spurs are frequently found at 
the origin of the radial sector (Plate XX XVIII, 115 and 116), or na 
