512 Mr. J. Wood on Variations in Human Myology. [June 18, 



females in the right arm, and in 1 male and 1 female in the left only. 

 In the left arm of No. 22, in which the extensor primi was altogether 

 absent, the secundi sent off a substitutory slip to the phalanx. In 

 the left arm of No. 33, a slip from the secundi was given to the first pha- 

 lanx, and one from the primi was sent forward to the ungual phalanx, 

 forming a mutual compensation (see fig. 8, c, d). 



33. Extensor indicis. — In the left arm of the female (No. 33), the sub- 

 ject of many abnormalities, this muscle was found to be quite doubled, a 

 tendon from each going to the usual insertion. The tendon only was 

 doubled in 3 males in both arms — and in 3 fe- 

 males, 1 in both arms, and 2 in the left only. Fig- 8 (Subject No. 33). 

 In the left arm of a male (No. 15) the muscle 

 arose from the radius, carpus, and interosseous 

 ligament, and not at all from the ulna. In both 

 arms of the female (No. 35) it arose in common 

 with an extensor medii digiti, from which also the 

 index received a third slip of tendon, in addition 

 to those from the double indicator (see fig. 8 a). 

 A double tendon or muscle to the indicator has 

 been found in 11 out of 102 subjects, viz. : — in 6 

 males, on both sides ; and in 5 females — 2 in both, 

 and 3 in the left arm only. 



34. Extensor poinds et indicis. — In one male 

 (No. 11), in the right arm, and in two females 

 (No. 32 & 36), in both arms, were found the 

 curious, muscle first described by the author 

 under this name. Arising between the extensor 

 secundi and extensor indicis, from the hinder sur- 

 face of the ulna and adjacent interosseous liga- 

 ment and intermuscular septum, the muscle ends 

 in a single tendon, which, passing in the common 

 extensor sheath, divides on the carpus into two 

 tendons. The inner is inserted either separately 

 into the base of the first phalanx^ or joins the 

 common extensor aponeurosis of the index ; while 

 the other passes outwards to join either the ex- 

 tensor primi or secundi internodii of the thumb. 

 In both the females its poUex-tendon joined that 

 of the secundiy while its index- tendon joined wholly 

 the common extensor in one, and sent part of its 

 fibres to the base of the first phalanx in the 

 other. 



In the right arm of the male subject (No. 11), the origin of the muscle 

 was peculiar and differed from all the other specimens. Instead of 

 arising from the ulna with the other muscles, it arose more superficially 



