. o/ Me Pron^^om (Antilocapra amerlcana). 403 



from the epidermisj the skin remaining complete underneath 

 them. 



Two other points in which the Pronghorn differed from all 

 the other known Bovidse were the furcation of the horns and in 

 the absence of the " false hoofs," as the stunted terminations of 

 the rudimental second and fifth digits of each foot are termed, 

 in which latter respect it resembled the Giraffes {Camelopardalis). 

 These three important modifications of structure, when taken 

 together, induced the author to believe that it would be neces- 

 sary to raise the genus Antilocapra to the rank of a family in 

 the series of Ruminantia, which he proposed to arrange some- 

 what as given in the subjoined table. 



Order ARTIODACYLA. 

 Division RUMINANTIA. 



I. Ruminantia phalangigrada. 

 Placenta diffusa. Stomachus tripartitus : dentes 



1 — I . . 1—1 1 6-6 ^ 5-5 



primores ^ziy canini j-:^, molares g^g aut ^3^ : 



pedes didactyli 1. Camelidce. 



II. Ruminantia unguligrada. 



a. Placenta polycotyledonaria. Stomachus quadri- 



, , . 0-0 . . 0-0 , 



partitus : dentes primores 535 ; canini ^3^ aut 



i^ ; molares ^-. 

 1—1' 6—6 



a'. Pedes didactyli, ungulis succenturiatis nuUis. 



fa". Cornua in sutura coronali posita, ossea, 

 brevia, pelle tecta 2. Camelopardalidce. 

 b". Cornua ex osse frontali orta basi ossea, 

 parte superiore cornea, furcata, decidua . 3. Antilocapridce. 

 h'. Pedes tetradactyli, ungulis succenturiatis 

 duabus. 

 c". Cornua ex osse frontali orta, basi ossea, 

 parte superiore cornea, non furcata, per- 



manentia ;••• 4. Bovidce. 



d". Cornua ex osse frontali orta, oranino 



ossea, decidua 5. Cervida. 



e". Cornua nulla, dentes canini marium 



exserti G. Moschida. 



b. Placenta diffusa. Stomachus tripartitus; dentes 



primores jEi? canini y5i. molares g^g; pedes 



tetradactyli ; cornua nulla 7. Tragulidce. 



In conclusion the author called attention to the geographical 

 distribution of the Ruminants, as shown in the subjoined table, 

 in which the geographical divisions employed were the same as 

 those used by the author in his paper on the distribution of 



