CHAP. XIII.] 



DIGITS : HORSE. 



367 



The right manus of the same animal came into the possession 

 of the University of Graz and was described independently. In it 

 also the metacarpal II was developed and bore a well-formed digit. 

 There was also a rudimentary metacarpal I beside it, having a 

 length of 5 7 cm., and a breadth of l'o cm. at the central end. [The 

 description is brief and makes no mention of a mcp. V : further 

 account promised.] Mojsisovics, Anat. Anz., 1889, iv. p. 255. 



(2) Two digits, one being formed by development of the digit IV. 



Cases of this variation are ex- 

 ceedingly rare. No. 540 is the only 

 instance known to me in which a 

 proper account exists. Most writers 

 on the subject make a general state- 

 ment that such cases exist, but give 

 no references. 



Horse, having a supernumerary 

 digit on the outside of each fore foot. 

 (Fig. 109.) The animal was from 

 Bagdad. The outer rudimentary 

 metacarpal (IV) was well formed and 

 of nearly even thickness throughout 

 its length. It bore a digit of three 

 phalanges and a well-formed hoof. 

 The hoof was elongated and is de- 

 scribed as being shaped like the hoof 

 of a cloven-footed animal. [The de- 

 scription is very imperfect, but two 

 good figures are given, from which 

 it may be gathered that the inner 

 metacarpal (II) was somewhat more 

 developed than in an ordinary horse; 



and it appears that both the inner 



and outer metacarpals were separate 



throughout their course, but whether 



they could be detached from the 



large metacarpal or were ankylosed 



with it is not stated. The carpal 



bones are not described, but the 



figure suggests that the unciform 



was larger than it normally is. It 



is not stated that the two feet were 



alike in details. The large hoof 



(III) is represented as of the normal 



shape.] Wood - Mason, J., Proc. 



Asiat. Soc. Bengal, 1871, p. 18, Plate. 



Fig. 109. Right fore foot of Horse, No. 540, the external metacarpal (IV 

 being developed, bearing a digit. 



(After Wood-Mason.) 



