66 MOSQUITOES OF NORTH AMEEICA 



In the males of the Sabethini it is usually the claws of the middle feet alone 

 that show sexual peculiarities, and even these may be but slight. With a very 

 few exceptions the claws are simple in both sexes and the male characters consist 

 of differences in the length and shape of the claws. In Wyeomyia trinidadensis 

 the claws of the middle feet of the male are nearly equal in length ; one of them, 

 however, is much stouter and more strongly curved, and the fifth tarsal joint is 

 deeply excised apically beneath. In Limatus durhamvi the claws of the male's 

 middle feet are similar to those just described, the last tasal joint, however, is 

 without excision and only slightly tapered towards the apex. In the male 

 Wyeomyia circumcincta the claws of the middle feet are unequal in length, the 

 large one sickle-shaped, the small one gently curved. In the male of Wyeomyia 

 smithii there is one large sickle-shaped claw and the small claw is represented by 

 a minute stout spine. In Sahethinus undosus the male has the claws of the 

 middle feet of nearly equal length ; however, one claw is deeply cleft and one of 

 its branches, instead of tapering to a point, is flattened and truncated at the tip, 

 the truncation bearing a series of very fine teeth. The claws of the middle feet 

 of the male Sahethes cyaneus are very similar to those just described; the 

 flattened branch, however, is much broader and covers the other, the point of 

 which projects slightly from below. 



In the Sabethini just discussed it is only the middle claws of the male that are 

 modified; the front claws are simple and equal. In the genera Joblotia and 

 Lesticocampa both the front and the middle claws are differentiated. In Job- 

 lotia digitatus the claws of the front and middle legs of the male are unequal but 

 simple, those of the front legs being the larger and more curved. In the male of 

 Lesticocampa lampropus the claws of the front and middle legs are unequal and 

 simple, bent strongly backward so that the tip of the large claw nearly touches 

 the fourth tarsal joint. 



In Johlotia trichorryes the claws of the front and middle legs of the male are 

 unequal ; the large claw of the front feet has a slender tooth while all the other 

 claws are simple. The claws of the male Lesticocampa dicellaphora are perhaps 

 the most remarkable of any mosquito. The front claws are unequal, the larger 

 with a tooth. The middle claws are also unequal ; the smaller is slender and 

 unarmed; the larger has along its under surface a comb, composed of about 

 twenty very long, slender, sharp teeth. 



The claws are supported by a membranous cushion which occupies the apical 

 portion of the last tarsal segment beneath. This cushion may be nearly obsolete, 

 as in the male of Uranotcenia, when the claws are inserted close upon the tarsus 

 and more or less ventrally. The cushion covers the ventro-apical excision of the 

 fifth tarsal joint and upon the size of this excision the development of the cushion 

 depends. On this account this cushion is well developed in most of the Culicini 

 and produced forward beyond the tarsus to support the bases of the claws. The 

 cushion is furnished with two, more or less lanceolate, chitinous pieces, the 

 flexor plates. These flexor plates have muscles attached to their bases and hinge 

 upon the tarsus ; apically they are attached to the bases of the claws. By traction 

 of the muscles the claws are drawn downward. When the cushion is well de- 



