548 . GEOLOGICAL SURVEY OF THE TEREITOEIES. 



the humerus and its relative length to the femur, are quite as in some of 

 the lemurs. The most marked dilBference is seen in the increased num- 

 ber of teeth ; but in this point it relates itself to the other Quadrumana^ 

 as the most ancient types of Carnivora and Ungulates do to the more 

 modern ; e. g., Hycenodom to the former, and Falceosyojys to the latter. 

 In its special dental characters it shows a close resemblance to small 

 types of the Eocene, which have been regarded as low Perissodactyles, 

 as Hyopsodus, &c. 



TOMITHEKTUM KOSTRATUM, Oope. 



Proceedings of the American Philosophical Society, 1872, p. 470, (published by the 

 author, August 7,) 1. c, 1873, (read April 18.) 



This species was about the size of the prehensile-tailed monkey, so 

 frequently seen in shows. The first and second premolar have but one 

 root, the base of the second being about the size of the base of the 

 canine. The latter are cylindric at base. The incisors form a parabolic 

 outline, and have entire edges, the middle pair transverse ones. Enamel 

 generally smooth, premolars somewhat striate ; an indistinct inner cin- 

 guium. 



lleasurements. 



M. 



Length of entire dental series, (straight) 044 



Length of symphysis mandibuli 020 



Depth ramus at second molar 010 



Length crown of second molar 006 



Width crown of second molar ; 0045 



Width between two second molars 014 



Width between two canines 005 



Width of ascending ramus above dental foramen 016 



Length of humerus 083 • 



Liameter of head 013 



Diameter of shaft at middle 0085 



Diameter of distal end, transverse 023 



Diameter of distal end, antero-posterior , . 0078 



Depth of olecranon 009 



Depth of ulna at coronoid 010 



Diameter extremity of radius, proximally 009 



Diameter extremity of radius, distally 010 



Length of ilium from acetabulum 042 



Width near crest 017 



Length of femur preserved 137 



Wid'th just below neck 017 



Width at middle Oil 



Width at extremity 019 



Width of trochlea 009 



Longest chord of condyles and trochlea 019 



The specimens on which this species was founded were found together 

 by the writer near to Church Buttes, "Wyoming. 



NOTHARCTUS, Leidy. 



Geological Survey, Montana, 1871, p. 364. 



This genus is but little known, but is probably one of those which as- 

 sociates characters of lower quadrumana with Cercoleptes and other 



