ART. 13. DESCEIPTIONS OF FOSSIL IKSECTS COCKERELL. 9 



THAUMASTOCLADIUS SIMPLEX Cockerell and Sandhouae. 



Mr. F. Muir believes that this should go in the Flatoidinse. So 

 far as he can judge from the figure, it appears thar the suture is 

 indistinct, perhaps because it lies very close to the cubitus, as it does 

 in a number of living species. Pie would then interpret it. as follows: 

 A large costal membrane with cross- veins, subcosta and radius free 

 to base or near base, media branching about middle, cubitus branch- 

 ing much more apically. " Your reference to Gaja is then much 

 more appropriate." The figure of Thaumastocladius is upside down, 

 as may be readily seen by comparing the description. 



LITHOPSIS DUBIOSA Cockerell and Sandliouse. 



This is also referred by Mr. Muir to the Flatoidinae, as is indi- 

 cated by the shape of the head and the position of the tegmina. In 

 this group the tegmina are carried nearly fiat horizontally, and the 

 fossil appears to have had them in this position. 



HETEROPTERA. 



DELPHAX SENILIS Scudder. 



Plate 2, fig. 3. 



Green River Eocene ; " Cathedral Bluffs south of Little Tommies 

 Draw, at point where samj^les were taken." (Winchester 17.5, 

 U.S.G.S.) Total length 2.5 mm.; tegmina 2.6 mm. long and .70 mm. 

 wide, uniform pale coffee-brown ; abdomen with a broad dark median 

 band, but basal and apical parts pallid. Close to D. veterum, Cock- 

 erell, but considerably smaller, with narrower tegmina. 



Plesiotype.—Cvit. No. 69186, U.S.N.M. 



DINIDORITES MARGIFORMIS Cockerell. 



An additional specimen is U.S.G.S. 219, with reverse 220, obtained 

 by Scudder in the Roan Mountains, Colorado. 



ODONATA. 



EPALLAGITES, new genus. 



Small, slender dragon-flies with dark thorax and hyaline wings; 

 abdomen very slender, Arculus at not quite a third of distance from 

 base to nodus ; basal space not crossed ; antenodal cross- veins numer- 

 ous, crossing both costal and subcostal cells, continuous from one to 

 the other, or almost so; two antenodals before arculus and one im- 

 mediately above it, as in Airifhi'pteryx ; upper section of arculus 

 long, as in Rhinocypha; probably over 15 cross-veins between level 

 of arculus and nodus, forming cells which are (in the case of a few 



