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dratus femoris. This and the foregoing are functionally analogical, as 

 they are both tensors of the capsular ligament. Gantzer has described 

 a third muscle, with a similar action, passing from the cartilage of the first 

 rib to the same destination under cover of the lesser pectoral. 



9. Extensor primi internodii pollicis et indicis of Wood I found in 

 one subject, in 1858, arising from the ulna below the extensor secundi 

 internodii pollicis, and above the extensor indicis, the tendon of which 

 latter muscle united with the indicial slip of the anomalous extensor, 

 and was inserted into the second and third phalanges of the index finger. 

 This muscle exists in the dog and fox. 



10. An extensor annularis proprius, which may be regarded as a 

 rudiment of an extensor digitorum brevis manus, I found in the left 

 hand of a female subject, arising from the dorsal aspect of the cuneiform 

 bone and annular ligament and heads of the fourth and fifth metacarpal 

 bones. The muscle extended forwards, and ended in a single tendon, 

 which was inserted into the inner side of the long extensor tendon of 

 the ring finger, about the base of its first phalanx. Another rudiment of 

 the short extensor of the fingers I found in a male hand, similar to the 

 foregoing, but passing to the middle finger only, and quite separate from 

 the interossei. Not unfrequently I have seen the dorsal interossei 

 sending off slips, which seemed as though representatives of the same 

 extensor muscle. 



11. In this class of irregularities I would place several instances of 

 double interossei in the hand, which 1 have at different times observed, 

 both involving the palmar and dorsal groups of muscles. The former I 

 have found doubled in four different subjects — the latter in one instance. 

 In this case there were two muscles lying in each inter-metacarpal 

 space, each inserted by a tendon into the corresponding side of the 

 finger. (This instance is reported in "The Medical Press," vol. ii., p. 413.) 

 The former cases likewise showed twin muscles lying on the palmar 

 aspect of each interspace, except that between the first and second 

 metacarpal bone, each inserted into the outside and inside of each finger, 

 respectively : in these cases the dorsal interossei were normal. There 

 are several anomalies of these muscles on record, but none of them in 

 anywise resemble the foregoing, which I would venture to suggest 

 might throw light on some points of the homologies of these muscles. 

 It has often been a matter of comment that there is a strange want of 

 symmetry in the arrangement of these muscles in the hand, as well as 

 a want of conformity in the attachments of the homotypical muscles in 

 the hand and foot This is accounted for by Mr. Wood, because, as 

 the middle finger in the hand is the most bulky, it is assumed as the 

 centre of motion ; and it has two dorsal interossei to produce its divari- 

 cations, and its divaricator to the pollex excludes from the third meta- 

 carpal bone the divaricator from the pollex of the second digit, and ob- 

 tains an origin for itself from the dorsal aspect of the second metacarpal ; 

 so, instead of being a palmar, it becomes a dorsal interosseous muscle; and 

 this is supported b}~ the fact that the transverse convexity of the dorsum of 

 the hand gives to the metacarpal bone of the middle digit a prominence 



