THE CRANE-FLIES OF NEW YORK PART II 755 



subcircular, or even broader than long. In Elliptera they are earlike and 

 very large. In Antocha a unique condition is found, in that the apparatus 

 is divided into eight stout filaments. In the Eriopterini and the Hexatomini 

 the horns are usually long and cylindrical or slightly flattened, and straight 

 or but slightly curved. There are numerous deviations from type, how- 

 ever. In Gnophomyia and some species of Gonomyia (alexanderi and 

 kansensis, for example), the horns are trumpet-shaped; in Gonomyia sul- 

 phur ella they are compressed and flattened into fanlike structures. In 

 several widely separated paludicolous genera, such as Ulomorpha, Pseu- 

 dolimnophila, and Prionocera, the breathing horns are split at their tips 

 into two conspicuous flaps with fimbriate margins, an obvious adaptation 

 to an existence in mud. Often the breathing horns are very small (as in 

 Elephantomyia, Teucholabis, and Trichocera) or even microscopic 

 (Dicranoptycha). Limnophila hyalipennis (Zett.) is described by Beling 

 (1886 : 198-199) as lacking the breathing horns, but this is presumably an 

 error of observation which may be due to a defect in the material studied, 

 or possibly the horns are sessile or reduced as in Dicranoptycha. In 

 some species (Erioptera, Eriocera) the horns are stout at the base but 

 taper rapidly to the acute points. In many Pediciini the tips of the 

 horns are expanded and usually obliquely truncated, with a row of 

 breathing pores around the margin. The tipuline breathing horns are 

 remarkably uniform in general structure, being usually elongated cylindrical 

 in shape, of moderate length, and with the tips slightly expanded. The 

 most conspicuous deviations from type are the short, flattened, and some- 

 what clavate horns of Tanyptera. 



The thoracic mesonotum is very convex, or gibbous in many species 

 (Limnobiini and some Hexatomini). In other species it is declivitous, 

 with a high transverse crest (Eriopterini). This crest may be armed 

 with numerous small spines (Helobia); from two to four powerful hooks 

 (Molophilus, some species of Ormosia, some species of Erioptera, Teucho- 

 labis); from six to eight tubercles set with stiff bristles (Gonomyia); or 

 abundant small setiferous tubercles on either side of the median line, 

 these being less conspicuous along the shoulder (most species of 

 Ormosia and of Erioptera). In Eriocera longicornis there is a median 

 spine or tubercle on the scutellum. In some Cylindrotominae the 

 metanotum bears spines. The extreme lateral or ventral margin is 

 produced into a blunt or somewhat pointed angle just above the wing 



