6 PROCEEDINGS OF THE NATIONAL, MUSEUM vou 66 



miles southeast of Navasota and half a mile south of Woods, Grimes 

 County, Texas. The remains had already been removed from the 

 ground when Doctor Francis learned of them. As is natural, when 

 persons undertake to collect such fossils without instructions or 

 previous experience, the remains suffered from the extraction. The 

 collection consists of teeth in good condition (except the loss of the 

 roots), portions of several upper tusks, a part of a lower tusk in a 

 fragment of a jaw, and parts of two tusks of a young mastodon. 

 From this same locality were collected some of the fossils which the 

 writer described in January, 1924,^° besides other species, not yet 

 determined. Rhinoceros bones are not uncommon. The remains 

 occur in the Fleming formation : and the writer concluded that this 

 belongs in the Upper Miocene. Doctor Francis deserves commenda- 

 tion for having rescued such- precious materials. 



2. Description of the premolar teeth 



What the writer takes to be the lower right and left third pre- 

 molars are in the collection, and they are in a fine state of preserva- 

 tion. It is doubtful if they were erupted, for they show no signs 

 of attrition. Photographs of these are here reproduced. The one of 

 the left side presents the grinding surface; that of the right, the 

 inner face (pi. 3, figs. 2, 3). 



The base of the crown of these premolars is oval and slightly 

 wider behind than in front. The tooth of the left side is 28 mm. 

 long and 20 mm. wide. The crown consists of two parts, the an- 

 terior of which, occupying seven-tenths of the length, forms a 

 transverse crest rising 18 mm. from the base of the crown; the 

 posterior part presents a low crest of two conules. The two parts 

 are separated by a very distinct transverse valley. The inner face 

 of the crown slopes away from the summits of the crests more slowly 

 than the outer face. The anterior crest is composed of two closely 

 appressed cones, the inner of which is the larger, although the two 

 are of the same height. This inner cone consists of three conules, 

 one in front of and one behind the principal conule. The hindmost 

 forms a broad ridge which descends into the transverse valley, par- 

 tially blocking it. In front, at the base of the anterior crest, is a 

 small but distinct fold of enamel forming a talon. There is no 

 trace of a cingulum on the sides of the crown. The hinder portion 

 of the crown, occupying three-tenths of the length, presents a crest 

 consisting of two low conules well separated. The inner of these is 

 the larger. Applied rather closely to the rear of this is a smaller con- 

 ule, whose hinder border merges into a sharp minutely tuberculated 

 ridge. The conule and the ridge form a sort of talon at the rear of 



w Proc. Biol. Soc. Washington, vol. 27, pp. 1-20. 



