GEOLOGICAL SUEYEY OF THE TERRITORIES. 365 



Lo]iMotlierium Ballardi. 



A second and smaller species, named by Prof. Marsh, from a jaw 

 fragment with teeth, found at Grizzly Buttes, Wyoming. The last 

 lower molar tooth measures scarcely 4J lines fore and aft, whereas in the 

 former species it measures 5^ lines. 



Titan OTHERIUM. (?) 



Titanotherium (?) anceps. 



Some remains of the largest mammal of the Bridger Tertiary forma- 

 tion have been referred with doubt by Prof. Marsh to the genus 

 Titanotheriimi. The animal was about two-thirds the size of the Titano- 

 tlierium> Froutij of the Mauvaises terres of White Eiver, Dakota. Per- 

 haps the remains I have referred to Palceosyops major may belong to the 

 same. 



E YEN-TOED PAOHYDEEMS. 



Elotherium. 



UlotJiermm lentis. 



A species of suilline pachyderms, indicated by Prof. Marsh and 

 founded on a jaw fragment containing a last molar tooth, from Henry^s 

 Fork of Green Eiver, Wyoming. The species was aboul^ half that of 

 Elotherium Mortoni of the Mauvaises terres of White Eiver, Dakota. 



PLATYaONUS. 



Platygonus Ziegleri. 



Another suilline pachyderm, indicated by Prof. Marsh, he refers * 

 to the Peccary-like genus above named. It is founded on specimens 

 obtained at Grizzly Buttes, Wyoming. The species was as large as the 

 Domestic Hog. 



BIEDS. 



Of remains of birds I have tletected no trace of bones, among the col- 

 lections of fossils, from the Tertiary formation of Wyoming, which have 

 been submitted to my inspection. 



Prof. Hayden exhibited to the writer an interesting specimen, con- 

 sisting of the impression of the distal extremity of a feather in a 

 fragment of shale, which was discovered among the Green Eiver shales, 

 so remarkable for the great number of well-preserved fishes they con- 

 tain. 



Bubo. 



Biiho leptosteus. 



Prof. Marsh, who has taken especial pains to seek for these rarest 

 of fossils, tlie remains of birds, reports the discovery of some bones in 

 the Tertiary beds of the Green Eiver Basin. One of these, from Grizzly 

 Buttes, he refers to an owl about two-thirds the size of the Great-Horned 

 Owl. The species is named as above. 



