of Fingers and Toes, and of the Phalanges, in Man. 87 
In girth, each is only a little less than the left-hand thumb. The 
twin thumbs diverge from each other by their proximal phalanges, 
and converge by their distal phalanges, and are webbed half-way. 
In extension, the distal phalanges become parallel; in flexion, their 
points come together by their edges, and give a firm nip. Hach 
can be flexed and extended separately when the other is held, but 
not otherwise. Flexion at the metacarpo-phalangeal joint is less 
extensive than usual. Motion at the carpo-metacarpal joint is free, 
and, in the movements of opposition, both of the thumbs move to- 
gether across the hand. In writing, the pen lies between the ap- 
proximated points of thetwothumbs. He is right-handed as usual. 
He states that variation in the number of the fingers or toes 
was previously unknown in the family. 
N , et. 13, Edinburgh (brought to me by my 
pupil Mr George Dickson), has an additional thumb on the left 
hand. The metacarpal bone is bifurcated for + to 4 inch, and 
forms two diverging heads for the two thumbs. The thumb next 
the forefinger is the larger of the two, and has nearly the usual 
length, but is not thicker than the last two divisions of the fore- 
finger. The lesser thumb at first diverges to the radial side, and 
then curves forwards at the metacarpo-phalangeal joint, which is 
somewhat loose. It has only one phalanx, which is 58 inch in 
length, the two phalanges of the greater thumb measuring together 
1d inch. The two thumbs move together in opposing the fingers. 
The lesser thumb is flexed and extended in common with the 
other, and has considerable power in flexion. 
Her mother states that variety in the number of fingers or toes 
was previously unknown in the family. 
4. W——G , et. 8 months, Edinburgh (kindly sent to me 
by Mr Edwards), has the thumb of the right hand double. The 
thumb next the forefinger is of good size, and has the usual num- 
ber of bones. The lesser thumb consists of one phalanx, which is 
attached, firmly but quite moveably, to the inner side of the proxi- 
mal phalanx of the greater thumb beyond its middle. It is about 
half the thickness of the greater thumb, is half the nail’s length 
shorter, and they are webbed together as far as opposite the begin- 
ning of the two nails. 
The mother states that the variety was previously unknown in 
the family. 
5. I am indebted to Dr Edward Robertson of Otterburn for a 
note of the case of T H , et. about 6 months, Northumber- 
land, who had an additional thumb on the right hand. It was rather 
loosely attached at the radial side of the metacarpo-phalangeal 
articulation of the greater thumb, which, again, was rather smaller 
than the thumb of the left hand. Dr Robertson lately removed 
the lesser thumb, and I find that it contains one phalanx only. 
The father, mother, and maternal grandmother, all state that 
nothing of the kind was before known in the family. 
6. My pupil, Mr Purves of Dryburgh, has procured for me a 
note, by his father, of the case of J , Berwickshire, a 
