DIPTER^ Linii6. 



Baron R. von Osten Sacken and Mr. Edward Burgess have given me 

 much assistance in perplexing points while studying tlie Oiptera here 

 recorded. 



DIFTER^ CYCLORHA.PHA. 13 racier. 



Family LONCH^EIDvC Loew. 

 LONCH^A Fallen. 



L0NCH.EA SENESCENS. 

 PI. 3, Fig. 18, 

 Lotichma senescent Scudd., Rep. Progr. Geol. Surv. Can., 1875-1876, 277-278 (1877). 



A portion of the body (excluding the head) too fragmentary to be of 

 any value and a pair of expanded wings faintly impressed on the stone com- 

 pose the remains of the single individual of this species. The wings are 

 rather slender, obovate and well rounded, with the neuration of Lonchsea 

 vaginalis Fall., as given by Westwood in Walker's " Diptera Britannica," 

 excepting that the basal cells do not appear to be quite so large in the fossil 

 species, and the fourth longitudinal vein is slightly more arched beyond 

 the larger transverse vein ; the costal vein is bristly ; the wing appeal's to 

 be hyaline, but there is an indication of a slight infumation along the larger 

 transverse vein ; it is covered with excessively iine microscopic hairs, which 

 also cover all the veins with a delicate pubescence ; with this exception the 

 first longitudinal vein is bare ; the larger transverse vein is slightly oblique, 

 and but little larger than the portion of the third longitudinal vein lying 

 between the two transverse veins. 



Length of wing, 4.6°"°; breadth of same, 1.8""°. 



Quesnel, British Columbia. One specimen. No. 17, Dr. G. M. Dawson, 



Geolosfical Survey of Canada. 



539 



