Tribe TEREBRA-NTIA. Latreille. 



Family TENTHREDINIDyE Leaeh. 



TAXONUS Dalilbom. 



Taxonus nortoni. 



PI. 10, Figs. 26, 27. 



A fairly preserved specimen and its reverse, showing a dorsal view 

 with most of a front wing, but neither legs nor antennae. The head and tho- 

 rax are dark, unusually dark for specimens on this stone, but the abdomen is 

 much lighter, almost uniformly so, but showing the sides a little duskier. The 

 veins of the wings and the stigma are uniformly dusky. The first discoidal 

 cell is almost uniformly rhombic, the cross-vein separating it from the sec- 

 ond discoidal cell being unusually long. The first inner apical nervure falls 

 exactly below the middle of the first discoidal cell and the lanceolate cell 

 has a strongly oblique cross nervure terminating opposite the inner end of 

 the same discoidal cell. 



Length of body, 7..5""" ; breadth of thorax, 2.5'""' ; length of wing, 7""°. 



Green River, Wyoming. One specimen, Nos. 22 and 140 (Prof 

 L. A. Lee). 



Family CHALCIDID^E Walker. 



DECATOMA Spinola. 



Decatoma antiqua. 



PI. 10, Figs. 20?, 31. 



Decatoma antiqua Scudd., Bull. U. S. Geol. Geogr. Surv. Terr., IV, 749 (1878). 



On the same stone as Lystra richardsoni, but at a slightly higher level, 

 is a minute chalcid fly. The wings are lacking, but the whole of the body 

 is preserved, together with the antennjE. The head is large, arched, and 



604 



