114 CONTEIBUTIOSrS TO CANADIAN PALEONTOLOGY 



TMs wing is 13"™ in length. The ratio of the breadth to the 

 length is as 1:2-7. In form, it departs slightly from P. separanda, 

 since the greatest width lies in the middle of the wing, the anterior 

 margin is not so strongly curved downward, and the basal portion is 

 not so much reduced. The radius extends scarcely seven-tenths the 

 length of the wing, and at the end shows only a very slight curva- 

 ture. The sector arises just above the first third of the length of the 

 wing and is very gently curved, bifurcating somewhat beyond half its 

 own length ; its anterior branch is strongly arcuate, rather long, and 

 fuses in the margin rather nearer to the posterior branch than to the 

 end of the radius. The radiomedial cross-vein lies nearer to the fork- 

 ing than to the origin of the sector, and exactly in the middle of the 

 wing. A little below the middle of the wing, the media separates 

 into two distinctly curved divergent branches. The cubitus with its 

 two branches, which curve strongly downward, does not reach quite 

 half the length of the wing. The mediocubital cross-vein is situated 

 rather more than twice as far above the radiomedial cross-vein as 

 the latter is above the forking of the media. The simiple anal vein is 

 slightly less curved than the cubitus. The wing appears to have been 

 very opaque in the costal region. 



Penthetria avunculus, sp. nov. Figs. 20 and 21. 

 Locality: Tulameen river, opposite Vermilion clifi — (August 6, 

 1906. L.M.L.). 



Pig. 20. — Penthetria avunculus, HandHrsch. 



There are two examples of this species, both rather imperfectly 

 preserved. This form appears to be rather similar to P. nana; but 

 seems to have had a more robust body and a smaller head, differences 

 that perhaps may be interpreted as sexual. If the forms were to be 

 separated, the distinction would rest solely on a difference in the 



