534 Mr. J. Wood on Variations in Human Myology. [May 23^ 



thumb, to be inserted with it into the extreme phalanx, and the inner, 

 smaller, was inserted separately into the hase of the^rs^ 'phalanx of the 

 index ^ outside of, and distinct from, the tendons of the common extensor 

 and indicator proper. The author has found the same arrangement in 

 the Yampire Bat, Dog, Cat, Hedgehog, and Babbit. Meckel found it in 

 the Bear, Coati, and Beaver. 



In its insertion, this specimen differs from those formerly described 

 by the author by joining the tendon of the extensor secundi internodii 

 pollicis. In the others it joined or substituted that of the extensor primi 

 internodii which was present and normal in the subject of the wood.cut 

 (fig. 5). This arm presents an extraordinary instance of multiplication of 

 these special extensor muscles of the hand. In a specimen of the above 

 muscle described by Macalister (p. 4), the indicial tendon joined that 

 of the indicator, and was inserted into the second and third phalanges 

 of the index. 



In one subject (jSTo. 11) the Extensor primi internodii pollicis was 

 altogether wanting on both sides. A small tendinous looking ligament 

 was attached to the styloid process of the radius and passed to the base 

 of the first phalanx of the thumb, which seemed to represent the lower 

 part of its tendon on both sides. It indicated an arrest of development 

 in the muscular germ above, and was unattended by any evidence of 

 diseased action, or any peculiarity in the muscular part of the extensor 

 ossis metacarpi pollicis, usually so closely connected with this muscle. 

 The occasional total absence of this muscle was noticed by Soemmerring 

 and Meckel. In one subject (No. 21) the extensor primi internodii 

 pollicis was entirely blended at its muscular portion with the extensor 

 ossis metacarpi, its tendon becoming free at the styloid process of the 

 radius. This has been observed by Theile. In two subjects (Nos. 20 

 & 34) the tendon of the same muscle sent a large portion (in the last 

 the chief portion) of its fibres to join that of the extensor secundi at 

 the base of the ungual phalanx. Soemmerring has observed this pecu- 

 liarity. Macalister found once in about nine subjects an opposite ar- 

 rangement to this, viz., the tendon of the extensor secundi giving a slip 

 to the base of the first phalanx. This has been also seen by the author 

 in cases of absence of the extensor primi internodii. 



In one female subject (No. 17) was found a large slip of the spinal 

 fibres of the Infraspinatus passing superficially to the rest of the 

 muscle aad to the teres minor, to be inserted into the lowest part of the 

 hinder border of the greater tuberosity. 



In a male subject (No. 14) was found, in the right arm, a fine speci- 

 men of the detached portion of the subscapularis, which has been de- 

 scribed by Professor Haughton under the name of Infraspinatus se- 

 cundus, and by Macalister under that of Sulscapulo-humeral or capsular. 

 It was quite detached from the subscapularis, arising from the border 

 of the scapular as a flat muscular band, 1 inch wide, crossed the long 



