868 Charles Paul Alexander 



from it. This probably represents the first anal vein in these species, 

 in which case all three anal veins would be accounted for. 



The cross-veins. — The usual cross-veins of the wins 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 (r) lies entirely in the radial field, and con- 

 nects Ri with either Ro or R-z +3, or it may lie exactly at the fork of the 

 last-named vein. The radial-medial (?--m) cross-vein connects either 

 Ri + 5 with Ml + as in most crane-flies, or i?5 with Mi + 2 as in Molophilus 

 (Plate XXXIV, 65-70), or Rs with Mi + 2 as in Tricyphona kuwanai oi 

 Japan and in the genus Rhampholimnobia discussed above. The medial 

 cross- vein (m) lies entirely in the medial field and connects either M2 or 

 Ml + 2 with Mz + 4. The medial-cubital cross-vein (m-cu) connects either 

 M or il/.T -I- 4 with Cui. 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 crane-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 columhiana there is a single strong cross-vein 

 in cell M. 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 like 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 XXXL 10-13) and many 

 Rhipidia in cell Sc; Helobia (Plate XXXVII, 98) and Dicranophragma 

 (Plate XXXIX, 139) in cell R.; Epheha (Plate XXXIX, 137 and 138) 

 and Idioptcra (Plate XXXVIII, 115) in cell M; Dicranota (Plate XLI, 

 167-169) in cell Ri, alongside of the r cross-vein; Discobola (Plate XXXII, 

 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 XXXVIII, 115 and 116), or in a 



