328 



MERISTIC VARIATION. 



[part I. 



* 



±86, 



radial digit or thumb had three phalanges in addition to the meta- 

 carpal, all the articulations being moveable. Relatively to the 

 others their digit was placed as a thumb. Left hand. The digit 

 corresponding with the thumb was composed of three phalanges like 

 that of the right side, and though finger-like in form it was 

 functionally a thumb. On the radial side of this 3-jointed digit 

 there was a supernumerary digit composed of two phalanges articu- 

 lating with the metacarpal bone of the 3-jointed thumb. This 

 supernumerary digit had a well-formed nail. The 3-jointed thumb 

 of the left hand was longer than that of the right hand (measure- 

 ments given), Windle, B.C. A., Journ. of Anat. xxvi. 1891, p. 100, 

 PL II. [Right hand, Condition II ; left hand, Condition III.] 



Man having 3 phalanges in the thumb of the left hand together 

 with a supernumerary digit. (Fig. 89.) This case in several 

 respects resembles the left hand of the subject described by Windle. 

 The four fingers were normal. The thumb stood in its normal 

 relations to them, but was finger-like in form, having three 

 phalanges in addition to the metacarpal. On the radial side of 



Fig. 89. 



Bones of left hand of No. 486, shewing Condition III. 

 (After Rijkebusch.) 



this 3-phalanged digit there was a supernumerary digit, having 

 two phalanges and a separate metacarpal, which articulated with 

 the head of the metacarpal of the thumb and the trapezium. In 

 the carpus of this hand there was a supernumerary bone which is 

 described as an os centrale. The bones and muscles of this limb 



