550 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 48. 



domestic races and breeds has been and is yet a much- discussed 

 question. Although some authors have held the opinion that the 

 domestic horse was introduced into Europe by westward-wandering 

 primitive men. there has been exhibited more recently a strong 

 tendency to regard all the forms of Equus cab alius as either the 

 descendants of a primitive race of this species or as the product 

 of the mingling of two or more races, all of which lived in Europe 

 and to all of which the name cdballus is to be applied. Lately there 

 has been shown again a disposition to withdraw from the abundant 

 Pleistocene forms some which are to be regarded as distinct species. 

 So far as this can be done safely it will greatly assist in clarifying the 

 situation. 



One who examines even only cursorily the literature on European 

 Pleistocene horses and on the derivation of our domestic horses must 

 be struck by the lavishness which has been exhibited in the applica- 

 tion of systematic names. Sanson recognized eight species, or races, 

 of existing horses belonging to the form known as Equus cab all u^ 

 and to these were given trinomial names: but before Sanson's time 

 Fitzinger described 5 distinct species: 23 races, whose names were ex- 

 pressed by trinomials ; and about 120 breeds, for which quadrinomial 

 names were coined. And the employment of quadrinomials appears 

 not yet to have ceased. 



Dr. Ewald TVust has published 1 a description and illustrations 

 of a fossil horse which he regarded as a new species. This horse had 

 been found near Siissenborn. Thuringia, in a deposit of gravel which 

 ITust believed had been laid down during the first interglacial stage. 

 This would correspond to our own Aftonian. The type of TYust's 

 species presents the cheek-teeth of the upper and the lower jaws. 

 On account of the extraordinarily large size of these teeth, because 

 of the complexity of the enamel of the lakes and especially of the 

 great inner valley, and because of the deep grooving of the pro- 

 tocone, and finally because of certain features in the lower pre- 

 molars and molars, the present writer believes that this horse forms 

 a species entirely distinct from anything to which the term Equus 

 caballus can with any kind of propriety be applied. 



One can hardly praise too highly several of the disquisitions which 

 have been written on the osteology of the horse, in which the utmost 

 patience and exactitude have been shown in taking measurements and 

 in correlating them. Xehring - especially indicated a Pleistocene ele- 

 ment, which has entered into the formation of the larger and heavier 

 races of domestic horses, and suggested the origin of the smaller 

 forms. Nevertheless, to the writer it appears that to Ewart and Stej- 



iAbliandL naturf. Gessellsch. Halle, vol. 23, 1901, pp. 287-296, pis. 6, 7. 

 2 Landw. Jahrb., vol. 13, 1884, p. 156. 



