NO. 2146. SOME AMERICAN FOSSIL INSECTS— COCKERELL. 97 



SCIARA FLORISSANTENSIS, new species (Mycetophilidae). 



Male. — Length 4.5 mm., wing 3.6 mm. ; veins not setose, venation 

 much Hke that of S. ahdita Johannsen, with a long E.^ ; dark brown, 

 legs dark, wings hyaline; first two antennal joints short and broad, 

 the following ones cylindrical, longer than broad, the third and 

 fourth each about 96 microns long and 76 broad; claspers formed 

 about as in 8. cueiimeris Johannsen, the apical part slender. The 

 following measurements are in microns : 



Radius before branching 1,280 



Ri beyond branching (apparent cross-vein) 960 



Distance on margin between ends of branches of radius, about 1,250 



Lower braucli of radius beyond cross-vein 2, 080 



R-M cross-vein 384 



Media before R-M cross-vein 960 



The delicate fork of media is wholly obliterated, but the subcosta 

 is distinct and well developed, though colorless. 



Miocene shales of Florissant (Geo. W. Wilson). 



Holotype.—C^t. No. 61995, U.S.N.M. 



CORDYLURA (s. lat.) EXHUMATA, new species (Cordjiuridae). 



Length, about 6.5 mm. ; abdomen, about 2.8 mm. ; wing, 6.7 mm. ; 

 hind tarsus, about 2.5 mm. ; hind tibia about the same ; hind femur 

 a trifle longer. Thorax, 3 mm. long, robust, dark, probably black in 

 life ; abdomen and legs paler ; abdomen short, formed as usual in the 

 family; wings dusky hyaline, not spotted, veins partly dark. An- 

 tennal arista long-plumose; auxiliary vein present, but very deli- 

 cate; none of the veins bristly; costa with a row of minute dark 

 spinules, not longer than diameter of costal vein (this row is single 

 and is not accompanied by delicate bristles, as it is in Scatoyhciga) ; 

 venation normal for the family ; first vein ending about 2.5 mm. from 

 base and 4.2 mm. from apex of wing; end of discal cell about 4.6 

 mm. from base of wing; first posterior cell about 0.8 mm. wide (deep). 

 Legs minutely hairy, without any long spines or bristles; femora 

 with dark spinules beneath, only at all large or conspicuous toward 

 apex ; tibiae spined at apex ; tarsi with dark spinules beneath. Dis- 

 cal cell on first posterior, 2,000 microns. 



Miocene shales of Florissant (Geo. W. Wilson). 



Holotype.— Cat. No. G1996, U.S.N.M. 



The insect has the appearance of a Scatophaga, but lacks the 

 strong armature of the legs seen in that genus. It is not a Cordylura, 

 as that genus is now restricted, but it is impossible to see all the char- 

 acters used to separate the genera in this family, so I do not attempt 

 to refer it to any genus of Becker's classification. 



Heer has described a Cordylura vetmta from the Miocene of 

 Croatia, but, judging from his figure, it does not belong to the 

 Cordyluridae. 



36399°— Proc.N.M.voI.51— 16 7 



