384 



DIPTERA. 



Fig. 303. 



distinct ocelli on the sides of the frontal tubercle. The species 

 appear in swarms, flying up and down in their mazy dances, 

 especially at twilight early in spring, though they may be seen 

 late in autumn and on warm days in winter. They live in de- 

 caying vegetable matter. Pedicia 

 is a gigantic crane-fly, embracing 

 the largest flies of the family, 

 and with Trichocera is the only 

 genus of this family having ocelli. 

 P. albivitta has hyaline wings, with the costa, the fifth longi- 

 tudinal vein and the central cross veins margined with brown. 

 The body is 1.4 of an inch in length. The lar^a of an Euro- 

 pean species lives in well water. 



The genus Cylindrotoma and its allies, resemble Tipula in 

 the course of the veins lying in the vicinity of the stigma, and 

 Osten Sacken illustrates the re- ^ 



semblances by the accompanying 



drawings, of which Fig. 303 rep- ^^ — 

 resents the venation near the 

 stigma of Cylindrotoma; Fig. 

 304 that of the European PJicdacrocera replicata^ closety allied 

 to the preceding genus, and Fig. 305 that of a genuine Tipula. 

 Ptychoptera is rather stout-bodied and has a singular mem- 

 branous spatulate organ, ciliated on the margin, which is 

 inserted at the base of the halteres. (Osten Sacken.) P. ru- 

 focinda O. S. is black with reddish bands on the feet. 



The larva of the European P. jycdudosa has a long respira- 

 tory tube at the end of the bod}-, which it raises to the surface 



of the water, and in the pupa 

 "one of the horny processes 

 which distinguishes the thorax of 

 all the pupae of the Tipulidce, 

 is enormously prolonged, like- 

 Fig. 303. wise, for the purpose of breath- 

 ing under water. (Osten Sacken.) The very singular genus 

 BiUacomorpha is an aberrant form, resembling the neu- 

 ropterous Bittacus. The antennae consist of twenty joints, 

 and the first joint of the tarsi is very much thickened, while 

 the abdomen is very long and slender. jB. clavipes Fabr. is 



Fig. 304. 



