3 4 8 ZOOTOMY. 



and inter-phalangeal articulations, and is inserted into the 

 middle and distal phalanges : divide and reflect. 



417. The extensor pollicis et indicis (ex.p.i), a 

 small, slender muscle lying in the groove between the radius 

 and ulna, beneath the common extensor : it arises from 

 the radius : its tendon enters the manus along with that 

 of the extensor communis, and divides into two, one of 

 which is inserted into the ungual phalanx of the pollex, the 

 other into the distal end of the metacarpal of the index. 



418. The abductor pollicis (ab.p), arising from the 

 outer surface of the shaft of the radius : its tendon crosses 

 that of the extensor carpi radialis, and is inserted into the 

 metacarpal of the pollex. 



419. The extensor quarti digiti (ex.d.^), the extensor 

 quinti digiti (ex.d.$), and the extensor carpi ulnaris 

 (ex.cp.u), three small, slender muscles arising close together 

 from the external condyle of the humerus, and passing 

 backwards behind the ulna to the manus. The extensor 

 quarti digiti is inserted into the ungual phalanx of the fourth 

 digit, the extensor quinti digiti into the base of the meta- 

 carpal and the proximal phalanx of the fifth digit, and the 

 extensor carpi ulnaris into the proximal end of the fifth 

 metacarpal : cut through and reflect all three muscles. 



420. The flexor carpi ulnaris (fl.cp.u), forming the 

 posterior edge of the fore-arm : it arises by an expanded 

 head from the inner face of the olecranon, and is inserted 

 into the pisiform : divide and reflect. 



421. Thepronatorteres(Fig. 65, C,pr.t), a small muscle 

 arising from the inner condyle of the humerus, and inserted 

 by a long tendon into the middle of the inner side of the 

 shaft of the radius. 



422. The flexor carpi radialis (fl.cp.r), a long, slender 

 muscle arising from the inner condyle of the humerus just 



