286 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
carpal bone; digits 1° and 1 are of nearly equal size, each composed of 
three phalanges and borne on a single large metacarpal. 1% and 1° are 
enclosed in the same hoof, which shows evidence of duplication. 
The phalanges of digit 1 are of normal size and form; the carpals 
are practically normal, but the trapezium articulates with the proximal 
nN. MM. 
Vis II. 
Fic. V.— Posterior view of left polydactyle manus, showing innervation. 14, 1, 
supernumerary digits; ”. m., median nerve; 1, first branch of median nerve supplying 
digits 1¢and 1%, 4 natural size. 
end of the compound metacarpal, and ends in a free distal process. 
The musculature of digit m is normal. The extensor proprius pollicis 
et indicis divides and is inserted into the distal phalanges of both 1% and 
1, The flexor perforans gives off an independent tendon to digit 1°. 
The innervation of the manus (Fig. V) is identical with that of cases 
in which the two extra digits are entirely distinct from 1 (Fig. Q). 
