TJPULIDJE. 267 



, are placed between the CULICID^E and SIMU- 

 LIID.S:, with sev r eral other families between them and their natural 

 allies the TIPULI>OE and LIMXOBIINJE, both of which are treated 

 in that catalogue as distinct families, CYLIXDKOTOMIDJE (as a 

 family also) following them. 



The DIXIDJK and KHYPHID^E are undoubtedly the most closely 

 allied families to the TIPULID^. 



The DIXID^E are distinguished from them by the absence of the 

 discal cell and the absence of the transverse thoracic suture. The 

 venation, though bearing a closer resemblance to that of some 

 PTYCHOPTEBIITS than to that of any other family, possesses a 

 system of its own, which a glance at the diagrams of wings will 

 at once show.* The filiform antenna, in which it is impossible 

 to discriminate the individual joints of the apical portion, is dif- 

 ferent from anything existing in TIPULII*^, except in Trichocera. 



The RHYPHIDJE possess a link with the bulk of the TIPTJLII^E in 

 the presence of a discal cell, which is absent throughout the rest 

 of the NEMATOCEBA. Their general structure and appearance (as 

 also those of the DIXIDA:) are similar to those of the TIPULIDTE,. 

 but they are distinguished by the contiguous eyes in the male, in 

 conjunction with the absence of the transverse suture on the 

 mesonotum. 



HEAD. In the large majority of the genera of TIPULID^E the 

 head is transverse, sometimes elongate, and rarely subglobular ; 

 the head itself, apart from the proboscis, being referred to in this 

 case; mostly bare, or nearly so, conspicuous bristles or spines 

 being absent, except that in some of the largest species the hairs 

 in places, such as the end of the proboscis, may be long and stiff, 

 but hardly worthy of being called bristles in the chaetotactic sense. 

 Short stiff bristly hairs are prevalent on the basal joints of the 

 antenna? in many species, but they are never conspicuous, nor of 

 sufficient importance to be of much value in the classification 

 of species. No conspicuous beard is ever present ; the frous, 

 vertex and back of the head bear short hairs, which in some 

 species of EEIOPTEEINI become comparatively long and shaggy. 



The eyes are rounded or oval, never or hardly ever excised or 

 cut away on the inner side above, giving a reniform (kidney- 

 shaped) appearance to these organs, as is the case with many 

 CULICID./E, CHIKONOMID^:, PSYCHODID^E, SIMULIID^E, and some 

 MYCETOPHILID.E. The eyes are almost always separated on the 

 upperside of the head by a broad frons, generally from one-third 

 to three-fourths of the entire width of the head ; the frons being 

 of equal width in both sexes or only slightly wider in the female. 

 On the underside of the head, the eyes are nearly always con- 

 tiguous or subcontiguous. It has been my good fortune to 



* Compare Dixa (PI. XII) and PtycAoptera (fig. 39, p. 275). 



