The Crane-Flies of New York — Part I 861 



strong fusions at these places. The more specialized forms have an 

 unusually strong series of cross-veins and deflections running trans- 

 versely or obliquely across the wing at about two-thirds its length and 

 generally in line with the ending of the radial sector and the inner end 

 of the cell 1st Ah (discal). This strong fusion is called the cord, and 

 a glance at almost any wing will enable one to pick it out immediately. 

 The genus Pedicia (Plate XLII, 175) has the elements of the cord in almost 

 perfect alinement, but very oblique, and here the principal parts entering 

 in are the basal deflection of Cth, the basal deflection of Mi + o, and the 

 r-7n cross-vein; in most crane-flies the deflection of Ri+5 adds another 

 strong element to the cord, while in many genera (as Antocha, Plate 

 XXXIII, 48, and Tcucholabis, Plate XXXIII, 52 and 53) the radial cross- 

 vein is so placed as to become still .another strong element. Very often 

 the radial sector enters in as the part nearest to the main radial vein 

 (Ri), and here the stress falls either on the sector or on R2 + 3, or on 

 both. As has been pointed out by Needham, in many species the closed 

 cell of the wing {1st M2) is swung directly across the path of the cord, 

 interrupting it like a ring on a line; the medial cross-vein and the outer 

 deflection of M3 are quite necessary to complete this ring, and they are 

 always present in such cases. It is only when the inner end of the 

 closed cell gets into alinement with the other elements of the cord, so 

 that the ring formed by the cell is no longer needed to strengthen the wing 

 disk, that the medial cross-vein is lost by atrophy. 



The longitudinal veins. — There are six or seven longitudinal veins, 

 named, respectively, from the front margin backward, the costa, the 

 suhcosta, the radius, the media, the cubitus, and the anal veins. 



The costa (C, fig. 128, a) forms the anterior margin of the wing. It is 

 usually much thickened, but thins out before reaching the wing apex. 

 I It is strongly united with the vein beneath it, the subcosta, by the humeral 

 cross-vein at the base of the wing. More distally other veins end in the 

 costa, such as Sci, Ri, and usually other elements of the radial field. 



The subcosta {Sc, fig. 128, a), a weak vein lying between the costa and 

 the radius, is often difficult to detect due to foldings and flexings of this 

 part of the wing. In generalized forms it is forked, the anterior branch, 

 Sci, going to the costa, and the posterior branch, Sc^ (the subcostal cross- 

 vein of the older authors), connecting with Ri. In the subfamily 

 Limnobiinae, Sci is usually present, and Sco may be close to its tip as in 



