370 



MERISTIC VARIATION. 



[PART i. 



549. Filly, two-year old, which had been born with left fore foot cleft 



like that of the Ox. Each of the two toes had three phalanges, which 



were completely separate as far up as the metacarpo-phalangeal joint. 



The division externally was carried to the same extent as in the Ox. 



The lower end of the great metacarpal III felt as if bifurcated like 



that of the Ox, so as to give separate articular support to the two toes. 



I'pper parts normal. The lesser metacarpals, II and IV, felt through 



skin, seemed to terminate rather lower down in left foot than in right, 



but this was uncertain. Animal examined alive. No attempt at 



shoeing had been made, and hoofs having become elongated forwards 



had had their points sawn off. The whole foot was much larger or 



more spread than the other. STRUTHERS, J., Edin. New Phil. Jour., 



1863, pp. U7'.i and 1'80. 

 *.550. Horse: right fore foot having phalanges bifid (Fig. 111). The limb 



was normal as far as the distal end of the metatarsal, except for some 



exostoses. The proximal phalanx was short and 



of great width; in its lower third it divided into 



two divergent parts, the divergence being more 



marked on the posterior face than on the anterior. 



Kaeh of these diverging processes bears a complete 



second and third phalanx. The third phalanges 



each bear hoofs, which are convex on the outer 



sides but tit together on the opposed surfaces, the 



external hoof being slightly concave on its inner 



face, while the internal is slightly convex. On 



the plantar surface, each toe bore a half-frog. 



The two large sesamoids, normally present in the 



Horse, are in this specimen united along their 



inner borders to form a single bone, which was 



iv 



") "> 1 . 



behind the upper part of the proximal 

 phalanx. Two small sesamoids lay behind the 

 third phalanx. A good deal of exostosis had 

 taken place in all the phalangeal bones. ARLOING, 

 M. S., Ann. Sci. Nat., Ser. V., Tome vin. pp. 

 G7 69, I'l. 



Foal : in right fore foot the large metacarpal divided 

 into two parts, each bearing a separate digit. The proximal 

 row of the carpus consisted of four normal bones, but the 

 distal row was composed of two bones only. The external 

 splint-bone (IV) was of normal proportions, but the internal 

 splint-bone (III had almost completely disappeared. The 

 large metacarpal (III) divided in its peripheral third into 

 t\\o equal cylindrical branches, each of which bore a digit 

 composed of three phalanges and bearing a crescentic 

 hoof. These two digits were bent across each other in a 

 shapeless way. DELPLANQCE, Mem. Soc. ccntr. </'.-)////<-. 

 <lii I >'']>. <lit 'Nord, a. 2, ix. Douai, 1866 ls(57, p. '_.:., 

 //. 1 1 !..../. 5. 



Mule, having two distinct toes on each fore foot. The 

 hoofs were shaped like those of the Ox. They were of 

 unequal length. JOLY, (.'<n}>t,'x Kaulng. 1860, p. 1137. [Perhaps a case belonging 

 to this section.] 



FIG. 111. Right 

 fore foot of Horse No. 

 550, from in front. 



sc, scaphoid, tp, 

 trapezoid. II, III, 

 IV, metacarpals. 111(7, 

 III b, internal and 

 external sets of pha- 

 langes representing 

 the digit III of the 

 normal. 



(After AKLOING.) 



