106 NORTH AMERICAN TIPULIDAE 



In my investigations of numerous individuals representing a 

 large number of species from within our faunal limits, the hypo- 

 pygium presents two characters which, independent of others, 

 I consider well-nigh characteristic of the genus. They are, 

 the ninth tergite never longer than wide, generally short, trans- 

 verse, impressed above mesially, the free margin incised or emar- 

 ginate in the middle and the lateral angles never acutely extended. 

 The outer apical appendages — upper of Snodgrass — are lan- 

 ceolate (broadly in P. oslari), acuminate, frequently attenuated 

 and incurved beyond the middle. In connection with these 

 hypopygial characters, others will invariably be present to estab- 

 lish the generic status of a given species. These having suc- 

 cinctly been stated by Alexander, 7 I merely wish to comment on 

 some and add others observed by myself: 



1. The short and stout proboscis, together with the rather 

 short and stout first antennal joint, mentioned by Schiner, 8 

 are present in all of our species (except californica, mentioned 

 hereafter) . 



2. The radical sector is longer, semi-oblique, with vein, S. c. 

 ending at some distance beyond its origin (Pachyrhinae 

 tipuloides), or else, short and oblique in a variable degree, with 

 vein S. c. ending in close proximity to its origin (Pachyrhinae 

 s. s.). 



3. The presence generally of S. c 1 , as a cross vein, in Pachyr- 

 hina 9 (absent in oslari, hybrida, partially atrophied in pachyr- 

 hinoides, calinota); absent in Tipula (present in oropezoides, dor- 

 solineata) . 



4. Cell M 1 , when sessile or very shortly petiolate, is character- 

 istic when present. A petioled cell M 1 occurs frequently and 

 varies considerably in length of its stem, not only in different 

 individuals of the same species, but even in the two wings of the 

 same individual. (Doane 10 ). According to Schiner, 11 speci- 

 mens of Tipula nigra occasionally occur, with cell M 1 sessile. 



7 Op. cit., p. 466. 



8 Op. cit., ii, p. 503. 



9 Prof. Needham in his "Key to the North American genera of craneflies" 

 (Report of the New York State Museum, 1907, p. 244), says under aa-b-Sc. 1 

 wanting-Tipulinae. In the footnote, same page, specifically includes Tipula 

 and Pachyrhina. 



10 Entomological News, 1908, p. 179. 



11 Op. cit., ii, p. 503 footnote. 



