AQUATIC INSECTS IN NEW YORK STATE 393 



boscis with round labellae, and only one half as long as the 

 incurved, four jointed palpi; antennae 15 jointed, the basal joint 

 disklike, the following joints each thickened at the base, in the 

 male plumose, the last two joints elongated and slender; the 

 eyes crescent-shaped. Thorax highly arched, without suture; 

 scutellum rather small; metathorax prominent. xVbdomen long 

 and slender, somewhat flattened, from the base to the middle 

 gradually widening, and again becoming narrower toward the 

 •end; hypopygium prominent, the ovipositor projecting. Legs 

 long and slender, the metatarsus longer than the following tar- 

 sal joint; claws small and simple. The wing veins and the pos- 

 -terior margin thickly haired; venation as in the figures. 



List of the North American species 



a I b i p e s n. sp. See p. 398. Ithaca N. Y. 



appendiculata Herrick. Minn. Geol. Nat. Hist. Sur. 188^1. p.lO. 

 Known only in the larval and pupal stage and may belong to some 

 •other genus. 



plumicornis Fabricius var. americana. (See subsequent pages for 

 synonymy) 

 Saranac Inn N. Y., Lake Forest 111., White mountains, N. H. (.Slosson), 

 Minnesota (Herrick) 

 punctipennis Say, Acad. Nat. Sci. Phila. Jour. 1823. 3:16, and 

 Compl. Wr. 2:43. Wiedemann, 1:14. Pennsylvania and New Jersey, 

 trivittata Loew, Berl. Ent. Zeit. 1862. p.l86. (Centur. 2, 1). Maine, 

 California, Alaska. 

 This is a synonym of punctipennis according to Giles in his 

 work Gnats or Mosquitoes. 



The larvae of but three North American species are known. 



To assist in separating the species which may be found later, 1 



have given in the table the characters of some of the European 



«pecies also. 



1 Antennae shortish and with a spine outwardly; anterior part 

 _ of the head is spiny; club-shaped bodies at the caudal end 



instead of claws appendiculata Herrick 



Antennae with four spines (2) 



'2 Ventral comb of the last abdominal segment with a row of 

 brushlike hairs; each consisting of five to seven bristles 



(European species) fusca Staeger 



Ventral comb consisting of a number of separate feathered 



hairs [pl.39, fig.6] (3) 



3 The pair of leaflike appendages [pl.39, c. fig.4] lying cephalad 

 of the labrum (/), at least one half as wide as long; ventral 

 comb of the last abdominal segment with 25 hairs (4) 



