72 



osborn: OLIGOCENE, MIOCENE, pliocene EQUIM3. 



with distinct cusp; (5) external eingula vestigial or absent; (6) postcanine diastema one-third shorter than K. praestans; 

 (7) symphysis shorter, more massive, incisors more robust. (8) Magnum-Mtc. II, articulation narrower; (9) feet about 

 one-eighth larger in all dimensions. The type and cotype include lower jaws of two individuals in slightly different degrees 

 of wear which unquestionably pertain to the same species. With one of the jaws is associated a considerable part of 

 the skeleton, all of one individual, including the cervicals except C 2-3, D 2-9, also three posterior dorsals, L 1, and part 

 of S 1, a few ribs, scapulae, pelvis, humerus, most of both radii and ulnae, magnum, Mtc. II, III of both sides, 1st median 

 phalange of fore foot, distal part of femur, one hind foot nearly complete, and parts of the other. 



(Matthew, 1913) While the affinity to Anchithcrium and Hypohippus is evident throughout, this animal equals 

 Hipparion in the length and slenderness of the hind limb and exceeds it in the length of the fore limb. The phalanges are 

 anchitheriine, as well as all the details of the upper limbs, feet, and vertebra?, and the proportions of the head and neck. 



Fig. 50. Kalobatippus agatensis Osborn, Amer. Mus. 14211. (Upper) Crown view of inferior grinding teeth of the 

 type, p2-m 3 of the right side. Natural size. (Lower) Right lower jaw of the type, containing p2-m 3 . One-half natural 

 size. 



The proximal phalanges resemble those of H. osborni and are much shorter and wider than those in the Protohippinae. 

 Other proportions are distinctive, namely: (1) the neck is one-fourth longer than in Hipparion whitncyi; (2) the animal 

 is microcephalic, the skull being remarkably small in proportion to the skeleton. 





Kalobatippus 



Hypohippus 



Hipparion 





agatensis 



osborni 



whitneyi 





Type, Am. Mus. 



Type, Am. Mus. 



Type, Am. Mus. 





14211 



9407 



9815 



V- m? 



118e 



.152 



.151 





225 



.201 



.212 





027 



.032 



.026.5 





041 



.038 



,045.5 





025.5 



.027 



.020 



Metatarsal III, length 



027 



.032 



.024.5 





039 



.044 



.044 



" " least width of shaft 



022.5 



.027 



.020 



Ill, 2, length 



030.5 



.035 



.027 



