THE CRANE-FLIES OF NEW YORK PART II 775 



especially of the setae on the cardines, are not the same. However, 

 the generic characters given above include all the species to which the 

 writer has been able to refer. 



Malloch (1915-17 b: 240-241) describes and figures an American Ptychop- 

 tera which is presumably P. lenis O. S. It agrees closely with the other 

 forms in most respects. The author indicates the mentum as having 

 three distinct parts, the median part being projected beyond the level of 

 the lateral parts and having more teeth (eight instead of six). Malloch's 

 specimens were taken in the Yellowstone Park, Wyoming, in August, 

 1890. From the locality data it is almost certain that the larvae belong 

 to the common Ptychoptera lenis of the western United States. 



Tonnoir (1919) describes a curious sexual dimorphism in the genus 

 Ptychoptera. 



Ptychoptera rufocincta 0. S. 



1859 Ptychoptera rufocincta O. S. Proc. Acad. Nat. Sci. Phila., p. 252. 



The species Ptychoptera rufocmcta is common around wet swales 

 and among open shrubbery. The adult flies are on the wing from 

 May to early July, and again .in late August and early September; they 

 may be double-brooded. In appearance they are conspicuously unlike 

 their relatives of the Bittacomorphinae, rather resembling certain large 

 fungus gnats (Mycetophilidae) . 



The larvae live in situations similar to those frequented by Bittaco- 

 morpha, and often occur in the same associations with larvae of 

 Limnophila (Lasiomastix) macrocera, Pilaria tenuipes, P. recondita, and 

 Erioptera chlorophylla, as well as with many Chironomidae, leeches, 

 nematode worms, and mollusks. In appearance they are strikingly 

 different from the larvae of Bittacomorpha, being pale, white or yellowish 

 white, with the body almost smooth, not covered with the dense trans- 

 verse rows of setiferous tubercles found in Bittacomorpha, and with the 

 pseudopods on the basal abdominal segments poorly developed. The 

 larvae of this species are smaller than those of Bittacomorpha, with the 

 head proportionately much smaller. In structural details, however, 

 they are rather similar to the larvae of Bittacomorpha. The larvae of 

 Ptychoptera rufocincta feed on the decaying vegetable matter in their 

 haunts. When fully grown, the pupa forms within the last larval skin, 

 and the elongate pupal spiracle is coiled about the mesothorax, as described 







