132 Barbour — New Nebraska Mammoth, JElephas hayi. 



In modern elephants and mammoths, the inferior mandibular 

 border is broad and round, and curves without angle into the 

 ascending ramus. Though much the same in E. hayi, it is to 

 be noted that the inferior border is somewhat subangular, 

 and that there is a distinct angle which is compressed to a 

 narrow edge posteriorly. This is quite unlike ordinary forms 

 of the genus Elephas. 



The mandible of E. hayi measures 29-J inches (750 mm ) from 

 the tip of the symphysis to the angle, while the mandible of 

 E. imperator, shown in figures 2 and 4, measures 21|- inches 

 (546 mm ), the difference being 8 inches (203 mm ). The depth 

 of the jaw at the coronoids is 9^ inches (24rl mm ), that of 

 E. imperator 10-J- (267 mm ). Though noticeably longer, the 

 jaw of the Crete mammoth is thinner than that of E. impera- 

 tor. The accompanying sections will give an idea of form, 

 and will show certain fundamental differences. 



The coronoid process is conspicuously robust, being 2£ 

 inches (70 mm ) through near its base, and an inch (25 ram ) near 

 the summit. It stands 4 inches (102 mm ) above the superior 

 mandibular border, and 2 inches (51 ram ) above the crown of 

 the teeth. It is set more obliquely than in other mammoths. 

 Its inner surface is deeply pitted, and. extends from the outer 

 to the inner alveolar border. The coronoids of mammoths 

 and modern elephants are weak and thin as compared with 

 those of E. hayi. 



The distinguishing character on which this new mammoth 

 must depend is derived, first of all, from the teeth. Especial 

 care was exercised to determine whether the teeth in the jaw 

 of E. hayi are penultimate or ultimate molars. If penulti- 

 mate, a successor should be in evidence in each ramus, but not 

 a fragment of a tooth or plate could be found in the cavities, 

 which were filled with compact sand and gravel ; nor could 

 any such fragments be found in the surrounding gravels when 

 screened. Undoubtedly the two teeth are the sixth molars, a 

 point of consequence in this connection. 



The teeth are those of a mature individual, with the crowns 

 well worn. Though well cemented and strong;, the teeth of 

 E. hayi are noticeably small. The postero-anterior diameter 

 is but 9 inches (229 mm ), and the greatest transverse diameter .3 

 inches (76 mm ). A similar tooth of E. imperator, shown in 

 figures 2 and 4, exceeds 14 (356 mm ) by 4 inches (102 mm ). The 

 dimensions of these teeth agree more closely with those of our 

 earlier Nebraska mastodons than with those of our mammoths. 

 The number of ti'ansverse plates is noticeably reduced, for 

 there are but 10 in one tooth, and 11 in the other, with no 

 plates missing. In E. imperator, there are 16 to 18 very thick 

 plates ; in E. columbi, 24 to 26, and even 28 moderately thick 

 plates ; aud in E. primigenius, 18 to 27 thin plates, although 

 fewer than 24 is rare. Ten enamel plates to the decimeter 



