SUPERFICIAL LAYER OF MUSCLES. 



283 



confine the extensor tendons. The ligament will be subsequently examined 

 more in detail. 



SUPERFICIAL LAYER OF MUSCLES (fig. 87). The muscles are arranged 

 in a superficial and a deep layer, as on the anterior part of the forearm. 



Fig. 87. 



Muscles : 



A. Supinator longus. 



B. Extensor carpi radialis longus. 



0. Extensor carpi radialis breris. 



D. Extensor communis digitorum. 



E. Extensor minimi digiti. 



F. Extensor carpi ulnaria. 

 a. Anconeus. 



H. Extensor ossis metacarpi pollicis. 



1. Extensor primi internodii. 



J. Extensor secundi internodii pollicis. 



K. Posterior annular ligament. 



L. Bands uniting the tendons of the common ex- 

 tensor on the back of the hand. 



K. Insertion of the common extensor into the 

 last two phalanges. 



Arteries : 

 a. Posterior iuterosseous. 



1. Radial. 



2. Posterior carpal arch. 

 d. Metacarpal branch. 



4. Dorsal branches of thumb and forefinger. 



SUPERFICIAL LAYER OF MUSCLES ON THE BACK OF THE FOREARM, WITH SOME VESSELS. 

 (Illustrations of Dissections.) 



The superficial layer contains seven muscles, which arise mostly by a com 

 mon tendon from the outer condyle of the humertis, and have the under- 

 mentioned position one to another from without, inwards ; the long supi- 



