600 TIPULID^. 



marginal cells, five posterior cells, and a discal cell. Auxiliary 

 vein ending at some distance beyond the middle of the wing, at, 

 or a little beyond, the inner end of the 1st submarginal cell ; the 

 latter cell shorter than the 2nd submarginal, its petiole about 

 equal to the length from the fork to the (sometimes indistinct) 

 marginal cross-vein, which is placed beyond the middle of the 

 marginal cell or just at the fork ; subcostal cross-vein shortly 

 before the tip of the auxiliary vein, joining the 1st longitudinal, 

 which ends some distance beyond the auxiliary veiu ; the 2nd vein 

 begins distinctly before the middle of tlie wing, the well arcuated 

 praefurca about equal iu length to the lo\\er branch ; an additional 

 cross-vein (in at least one North American species) occasionally 

 found in the 2nd submarginal cell ; 3rd vein origiiaating rather 

 sharply from the 2nd just anterior to the fork, practically straight, 

 its base, the anterior cross-vein, and the basal side of the discal 

 cell more or less in a line; discal cell pentagonal, broader distally, 

 its basal end rectangular, its distal sides forming an angle. " The 

 pentagonal shape of the discal cell plainly shows that it is the 

 forking of the posterior branch of the 4th vein which forms one of 

 its sides " {Osten ^acken). Five posterior cells, of which the 1st is 

 subequal to the 2nd submarginal in length, the 2nd varies in 

 shape with the species, the 3rd and 4th are subequal, the 5th 

 normal ; posterior cross-vein a little before or after the base of 

 the discal cell ; the 5th, 6th, and 7th longitudinal veins nearly 

 straight. 



Range. Previously known only from JN'orth America. 



The characters which distinguish this genus from the allied 

 genera, Paracladura and Cladurokles, may best be shown by the 

 following table : — 



A. Subcostal cross-vein placed near the tip of 



the auxiliary vein. Discal cell present, 



its proximal end rectangular. Antennal 



scape long, normal ; flagellum of fourteen 



oval joints. The 7th longitudinal vein 



normal Cladura, Os. Sac* 



AA. Subcostal cross-vein placed very far before 



the tip of the auxiliary vein, just after the 



origin of the 2nd vein, near the middle 



of the -wing. 

 B. The 1st longitudinal vein nearly as long 

 as the anterior branch of the 2nd vein, 

 ending close to it near the wing-tip. 

 Marginal cross-vein placed soon after 

 tlie fork of the 2ud vein, at a consider- 

 able distance from the tip of the 1st vein. 



* See my " Revis. Orient. Th'ulid.e" (Rec. Ind. Mus. vi, p. 285) with 

 regard to Chidoneura, a fossil genus figured bjNeedbam, which appears to 

 have been the immediate ancestor of this group of genera. 



