454 



NORTH AMERICAN INDEX FOSSILS. 



sented in the Oligocenic beds of Florissant, Colorado. Here occur 

 Jupiteria charon Scudder (Fig. i753-i754),Lithopsyche styx Scud- 

 der, Nymphalites obscurus Scudder (Fig. 1755), Prodryas perse- 



FiG. 1760. 



Barbarothea Jiorissanti^ general appearance of the fossil ; Oligocenic, 

 Florissant, Col., natural size. ( After Scudder. ) 



phone Scudder (Figs. 1 756-1 757), Prolibythea vagabunda Scud- 

 der (Fig. 1758), Psecadia mortuella Scudder, Stolopsyche liby- 

 theoides Scudder (Fig. 1759), and Barbarothea florissanti Scud- 

 der (Figs. 1760-1761). 



Barbarothea florissanti. 

 by head enlarged. 



Oligocenic, Florissant, Col. 

 Xf. (After Scudder.) 



Order DIPTERA Linnaeus. 

 {Flies.) 

 With the fore wings only prominent, membranous, narrow and 

 veined, while the hinder wings are reduced to clubbed filaments. 

 Longitudinal veins of wings sparingly branched, cross-veins few ; 

 C marginal, Sc simple, Rs forked, M forked once or twice, 

 Cii forked singly; anal furrow seldom developed, anal veins i to 

 2, often rudimentary. About 44,000 Recent and 1,550 Tertiary 

 species are known, 125 of them American. Flies have been found 

 as far back as the Lias. In America the division Cyclorrhapha is 



