96 Dr John Struthers on Variation in the Number 
than to the outer side of the fifth toe. Mr Murray removed the 
supernumerary fingers in July 1862. 
A brother has the same variety. The grandmother, on the 
father’s side, had the same variety; also a sister of the father’s. 
Section 3.—DIMINUTION IN THE NUMBER OF THE DIGITS. 
21. Dissection of Three Limbs of a Child, presenting Diminution in 
the Number of the Digits. 
The child was born with the right hand presenting only 
two fingers, webbed together ; the right foot presenting but 
three toes; and the left foot with the fourth and fifth toes 
united at their base. J was indebted to the kindness of Dr 
Keiller for obtaining the limbs. I have no history to the 
case, but have thought it worthy of notice from the oppor- 
tunity of ascertaining by dissection how far the variation 
affected the deeper parts—the bones, muscles, and nerves. 
(1.) Dissection or Hanp.—Externally there are two digits, one 
on the radial side considerably thicker than the other. It will be 
convenient to speak of the first as the pollex, and of the other as 
the little finger. They are webbed to the end, presenting a notch 
at the end on the palmar aspect. The nails are distinct, but close 
together. The palm is the same breadth as the forearm, and gra- 
dually tapers into the fingers. Both palm and fingers have the 
usual length in proportion to the forearm. 
Bonrs.—EHach digit has only two phalanges, the proximal about 
twice the length of the distal. There are two metacarpal bones. 
The four bones of the proximal carpal row are present, the second, 
or semilunar, small. ‘The second row of carpals is represented by 
two bones, which are coalesced with, or prolonged from, the first 
row. The piece supporting the ulnar metacarpal, corresponds in 
position to the unciform, and is fused with the cuneiform. The 
piece supporting the radial metacarpal is fused behind with the 
scaphoid, and may represent the os magnum, trapezoid, or trape- 
zium, or all three fused together. The bones and joints of the 
forearm are fully developed. 
Muscius.—All the muscles of the forearm are present except — 
one. The pronators and supinators are unusually large, as is also 
the Flexor Carpi Ulnaris. The Flexor Sublimis Digitorum is small, 
wants its radial origin, and ends in two tendons; one joins the 
tendon of the deep flexor, which goes to the little finger, the other 
ends in the annular ligament. The Flexor Profundus Digitorum 
is full sized, and ends in two tendons; one, the larger, ends in the 
annular ligament, the other forms a strong flexor tendon, going on 
to the distal phalanx of the little finger. The latter is joined at 
the wrist by the tendon of the superficial flexor, which is here 
pierced by the deep tendon, after which the two are incorporated. 
