36 PROCEEDINGS OF THE NATIONAL MUSEUM. vor«. 59. 



which is along the inner margin, while its outer margin is more than 

 halfway to outer margin of elytron. 



Eocenes. "Back of house at Smith's ranch, shale of Green River 

 formation with thin beds oil-shale interbedded." (Winchester 

 17-3. U. S. G. S.). Colorado. A pretty little species, congruous 

 with modern Lebia in every respect. A species of Lebia (L. amissa 

 Heyden) has been recorded from the Oligocene of Germany. 



Holotyiye.— Cut. No. 66928, U.S.N.M. 



Family SCARABAEIDAE. 



MELOLONTHITES AVUS, new species. 



Plate 8, fig. 4. 



A melolonthoid beetle preserved in ventral view, without the head. 

 Length as preserved about 13 mm., of which 5 mm. is posterior to the 

 hind legs ; width in region of hind legs about 7 mm. ; all the femora 

 very robust, the hind ones fully 1.5 mm. across; middle legs con- 

 tiguous at base; middle tibiae about 2.4 mm. long, not specially 

 enlarged or spinose, but with well-developed spurs; first joint of 

 middle tarsus only about 6 mm. long, second and third joints shorter; 

 hind tibiae simple, with a longitudinal ridge, apex moderately ex- 

 panded, ending in a short spine externally. 



Eocene. U. S. G. S. 894, White River, Colorado. Heer used the 

 term Melolonthites for fossil melolonthine or Pleurostict Scarabaeidae 

 of uncertain generic position. The present insect is of interest as 

 indicating the existence of this type of beetle in the American Eocene. 



Holotype— Cat. No. 66929, U.S.N.M. 



Family CALANDRIDAE. 



SCIABREGMA TENUICORNIS, new species. 



Plate 8, fig. 1. 



Length, 5.6 mm.; prothoracic process extending about 640 p. 

 beyond head, fingerlike, slender, and curved, fully three times as 

 long as thick; eyes rather large and round; beak as in S. rvgosa 

 Scudder; upper margin of prothorax straight in lateral profile, front 

 of head to posterior end of prothorax 2 mm. ; surface of prothorax 

 rugosopunctate ; legs apparently as in 8. rugosa; elytra 3 mm. long 

 and 1.5 wide, with nine rows of very distinct punctures; about the 

 middle the rows are a little more widely separated than the consecu- 

 tive punctures in a row, and the interval between the latter is about 

 equal to the width of a puncture. 



Eocene of Colorado. "Back of house at Smith's ranch, shale of 

 Green River formation, with thin beds oil-shale interbedded." (Win- 

 chester 17-3. U. S. G. S.). In white rock. A beautifully preserved 

 specimen, evidently congeneric with Scudder's #. ruaosa from Roan 



