1913] Cockerell — The Genus Phryganca (Trichoptera) in the Florissant Shales !'.5 



THE GENUS PHRYGANEA (TRICHOPTERA) IN THE 

 FLORISSANT SHALES. 



By T. D. A. Cockerell. 

 The University of Colorado. 



If it receives anything like the treatment it deserves, I liner's 

 magnificent work, Die Trichoptera des Baltischen Bernsteins, will 

 create much new interest, not only in the Trichoptera of amber, 

 but in the general history and classification of the group. Among 

 other things, it shows that as far back as the oligocene in Europe 

 the genus Phryganea was very well represented, no less than seven 

 species having been discovered in amber. When we consider that 

 only 20 or 21 recent species are known in the world, it appears 

 probable that in mid-tertiary times it was considerably richer in 

 forms than at present; but the modern Neuronia, with quite 

 numerous species, may be taken to represent an offshoot from the 

 Phryganea of the tertiaries, some of the fossil species possessing 

 more or less evident Neuroma-like characters. 



In the Miocene shales of Florissant Colorado, Phryganea is 

 represented, so far as at present known, by two species. One of 

 these was long ago described by Scudder; the other is new. In 

 addition, Scudder described a Neuronia evanescens, but its reference 

 to Xeuronia is doubtful. No definite idea' of its venation can be 

 gained from Scudder's figure, but his description is more explicit. 

 Vein R2 leaves the discoidal cell "close to the base," a condition 

 approached by the amber species Phryganea longirostris Hagen. 

 On the other hand the discoidal cell is comparatively short, as is 

 usual in Neuronia, while the R-M cross vein is "widely separated " 

 from the end of the discoidal cell, that is, considerably beyond it ; 

 an approach to the latter condition is shown by the amber species 

 P. egregia Ulmer and P. picea Pictet. An exact drawing of the 

 venation of A. evanescens, based on Scudder's t} r pe, is much to be 

 desired. 



Phryganea labefacta Scudder. 



I have before me a very well preserved anterior wing, collected 

 by my wife at Station 17. It is 19j mm. long, and a little over 

 7| broad; the discoidal cell is 6^ mm. long; end of discoidal cell 



