100 Dr John Struthers on Variation in the Nwnber 
PART IL—VARIATION IN THE NUMBER OF PHALANGES. 
Section 1—DIMINUTION IN THE NUMBER. 
22. Case in which all the Fingers and Toes want a Phalanx, in 
several Members of a Family. 
I am indebted to Dr Oswald H. Bell of St Andrews for 
the description and history of this case, and for affording 
me an opportunity of seeing the boy. 
David M——, et. 18, St Andrews, wants a phalanx in each of his 
fingers and toes, and has a brother and sister similarly formed. The 
two hands are precisely similar. The thumb consists of a short 
metacarpal bone (§ inch in length) and of one phalanx, 1} inch 
in length, the joint between them being loose, as if composed of 
some soft intermediate tissue. The fore finger is so much longer 
than the others as to suggest the appearance of a hand in the act 
of pointing. This is due to the greater length of its metacarpal 
bone, which is 3 inches in length, while the next two metacarpals 
are under half that length. ‘The metacarpal of the little finger is 
just 13 inch in length, but, from its obliquity, does not project so 
far as the fourth. The proximal phalanx of the fingers measures, 
in the index 12, in the middle 12, in the ring 1, in the little 
finger 12; the distal phalanx, in the index and middle, 3, in the 
ring and little fingers § inch. On the left side, the distal phalanx 
of the index finger is proportionately shorter. Except in the case 
of the fore finger, the five digits present their usual relative pro- 
jection. The metacarpo-phalangeal joints, especially of the index 
and middle fingers, are considerably sunk behind the web, and are 
loose, while the joint between the two phalanges does not bend down 
with the usual degree of angularity. 
He can easily seize and retain minute articles as a needle or pin, 
between the thumb and index finger, and can write with compara- 
tive ease. Being a groom, he can drive tolerably well, though he 
is apt to let the reins slip, being unable in the usual way to form 
the digital hook which the third phalanx naturally completes. 
The feet are well formed as far forward as the distal ends of the 
metatarsal bones. ‘The toes are short, pulpy, and very loosely arti- 
culated. The lesser toes have two phalanges each, and are much 
turned up at the interphalangeal joint; the great toe has its usual — 
proportionate greatness, but, like the thumb, has only one phalanx. 
The pads below the anterior end of the metatarsal bones, behind 
both the great and lesser toes, are more developed than usual. No 
the second toe as an occasional occurrence only. The tendinous slip com- 
monly described as passing between the Flexor Longus Pollicis and the 
Flexor Longus Digitorum, in the sole of the foot, is nothing less than a tendon 
from the former to at least the second toe, of good size when the proportionate 
size of the two toes is considered. It is, normally, the principal flexor tendon 
of the second toe, and the first lumbricalis muscle is attached chiefly to it. 
(See communication by the author to the Edin. Medico-Chirurgical Society, 
“ Edin, Medical Journal,” July 1863.) 
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