398 PROCEEDINGS OF THE ACADEMY OF [June, 



caudal tibiae are uncinate; smooth, sharp, and hard. Pantel has 

 also discussed the peculiarities of the distal (or fourth) internal spine 

 of the caudal tibia in his paper, where he has also given an excellent 

 figure of the spines and spurs of the caudal tibia in the male and 

 female of Nemobius Uneolatus Brulle. 



In the species having the disto-ventral spurs equal in length, the 

 internal dorsal and median spurs have lateral fringes of hairs on these 

 spurs more prominent and regular than in the other species. 



Comparison with Other Genera. — When compared with the genus 

 to which it is most nearly related, Paranemohius Saussure, we find 

 that Nemobius can be easily separated by the following characters: 

 the lateral lobes of the pronotum are quadrate, not oblique; the 

 tegmina of the male are provided with a tympanum; the vertex is 

 slightly convex, not excavate and rostrate; the caudal tibiae are each 

 armed with six, not five, distal spurs. The genus of next nearest 

 relationship is Caconemobius Kirby, which differs in the lateral lobes 

 of the pronotum which are not quadrate, the organs of flight which 

 are absent and the cephalic tibiae which have no tympanum. From 

 the other more nearly related genera, Nemobius may be readily 

 separated by the characters found in the caudal tibiae which are 

 armed with long, mobile, pilose spines and in the caudal metatarsi 

 which are neither sulcate nor serrate dorsad. 



Distribution of the Genus in North America. — The northern boundary 

 of the range of the genus is known to extend from Prince Edward 

 Island westward across Canada to Calgary, Alberta; from the latter 

 locality it has been found southward in the Yellowstone National 

 Park and the Salt Lake Valley in Utah, these localities showing its 

 extreme western distribution until southern Utah is reached, in which 

 latitude it has been taken at St. George, Utah, Las Vegas, Nev., and 

 the Panamint Valley in California to the Pacific coast at Los Angeles. 

 The genus is apparently found everywhere else in the United States 

 and Mexico south to the Isthmus of Panama, although the very few 

 records from southern Mexico, Nicaragua, and Costa .Rica may 

 possibly indicate that in these southern regions the genus is very 

 scarce. In the West Indies the genus has been taken in the Bahamas, 

 Cuba, and Granada. 



We consider the northern distribution of the genus in the Dominion 

 of Canada probably limited by the spruce belt only, but so little 

 work has been done so far north that nothing definite can at present 

 be stated. No specimens have been taken in Arkansas, Oklahoma, 



