Cook — New Proboscidean from the Lower Miocene. 183 



Art. XXI. — A New Proboscidean from the Lower Miocene 

 of Nebraska y by Harold James Cook. 



* G-omphotherium conodon sp. nov. 



lis the collections of the writer are two broken teeth (No. 

 HC 176) found in the summer of 1906 in the lower part of the 

 Upper Harrison beds, near Agate, Sioux County, Nebraska. 

 Although averse to founding new species on fragmentary 

 material, the type here represented seems quite important, and 

 as the Upper Harrison beds have been vigorously searched by 



Fig. 1. 



several parties during the past three years and no other 

 evidence of this unexpected form has been secured, a descrip- 

 tion is here given. 



The teeth are unworn, and may be a part of the milk denti- 

 tion, but are quite different from any described species. They 

 are simple bunodont teeth, with a very heavy crinkled cin- 

 gulum, which tends to develop into cusps as in other probos- 

 cideans. Though apparently somewhat more robust, the teeth 

 are essentially more simple than those of Palceomastodon. 

 They have only a slight roughness on the sides of the 

 cusps, where P akeomastodon has a distinct tendency toward 

 a crest. The tubercles or cusps are relatively low and blunt, 

 much like those of the Eocene proboscideans. The enamel is 

 very much thinner than in any known American type. 



* Gomphotlierium Bnrnieister, 1837 =Tetrabelodon Cope, 1884. 



