AQUATIC IXSECTS IX XEW YORK STATE 331 



11 Thorax enlarged; abdomen usually with 



long hairs; usually a complex respira- 

 tory apparatus at the anal end C u 1 i c i d a e 



Body much elongated (12) 



12 Last segment of the abdomen with two 



fleshy points R h y p h i d a e 



Last segment tapering, often with a few 

 long hairs. Body snakelike, segments of 

 nearly uniform length. (Oeratopogon) C h i r o n o m i d a e 



13 With anal prolegs and blood gills. (Chi- 



ronomus, Tanypus, etc.) C h i r o n o m i d a e 



Without anal prolegs; a broad abdomen, 

 with a terminal sucker; head with a 

 pair of fanlike organs (black flies) S i m u 1 i i d a e 



14 With rudimentary mouth parts; body with 



13 segments; peripneustic (i. e. spiracles 



on the median segments). Gall gnats C e c i d o m y i i d a e 



With biting jaws. Head incomplete, 

 small, retractile, not containing nerve 

 ganglia; 12 body segments; posterior 

 stigmata usually with some fleshy fila- 

 ments (crane flies) T i p u 1 i d a e 



ri'pac 



1 Prothoracie spiracles, if present, borne on 



appendages (Nematocera) iiii 



Prothoracie spiracles sessile B r a c h y c e r a 



2 Nonaquatic. Leaf miners or gall makers 



(Cecidomyiidae); larvae living in fungi 



(Mycetophilidae); larvae living in the 



earth (Bibionidae); larvae living under 



bark (some Ceratopogon) 



Aquatic or semiaquatic (3) 



4> Pupae in a fibrous cocoon .(4) 



Without cocoon, sometimes in the old lar- 

 val tube (5) 



4 Cocoon cornucopialike, the coarse thoracic 



filaments of the pupa projecting. These 



filaments are tisually few in number S i m u 1 i i d a e 



Thoracic filaments of the pupa if present, 



entirely within the cocoon, the latter 



usually subcylindric Some C h i r o n o m i d a e 



3 Body convex, hard shelled, and attached 



limpetlike to the rock (6) 



Not attached nor limpetlike (7) 



■6 Shield-shaped, flattened. Thoracic breath- 

 ing tubes are subcylindric-i Some Psycho didae 



iSee Professor Kellogg's paper in Eiit. Xews, Feb. 1901. 



