766 



THE NERVES. 



Fig. 351. 



When it reaches the interstice of the triceps and anterior brachial, it crosses the limb 

 above the outer face of the elbow, and divides into two series of terminal branches. 



The muscular branch enters beneath 

 the muscles on the anterior face of the fore- 

 arm. The cutaneous bifurcates imme- 

 diately: the smallest branch, passing in- 

 wards, extends beyond the bend of the 

 elbow, lies at the inner border of the median 

 subcutaneous vein, and is distributed to the 

 lower moiety of the fore-arm, the thumb, 

 and internal border of the index digit. The 

 largest lies at the outer side of the median 

 subcutaneous vein; it sends a recurrent 

 ramuscule to the bend of the elbow, and, at 

 the elbow, detaches three filaments to the 

 first, second, and third dorsal intermeta- 

 carpal spaces ; these filaments bifurcate at 

 the dorsum of the digits to constitute the col- 

 lateral dorsal nerves. The first metacarpal 

 nerve anastomoses, by a fine transverse 

 branch, with the ulnar ramuscule that 

 constitutes the external dorsal collateral of 

 the small digit. 



To resume : the radial of the Dog gives 

 branches to the dorsal face of all the digits, 

 except the external border of the first digit, 

 or auricularis. 



In the Cat, there are some differences. 

 The internal branch of the radial sometimes 

 lies with the external branch ; it is placed 

 at the inner border of the metacarpus, gives 

 off a filament to the dorsal face of the thumb, 

 and afterwards forms the internal dorsal 

 collateral nerve of the index. The external 

 branch leaves the anterior face of the carpus, 

 and is situated at the origin of the third 

 interosseous space, where it divides into 

 three metacarpal branches ; the external of 

 these is very fine, and directed obliquely 

 outwards, anastomosing with the dorsal 

 branch of the ulnar, between the first and 

 second digits. 



NERVES OF THE PALMAR FACE ; DOG. The median o f the J) og i s uri ited to the 



A, Trunk of the median dividing into six ulnar as far as the lower fourth of the arm ; 

 branches; Bl, Branch of the superficial it is situated behind the humeral artery, 

 nervous arch ; B2, Branch disappearing on and the filament it receives from the mus- 

 a vessel ; s3, B.4, Branches uniting Avith culo-cutaneous joins it at a short distance 

 the corresponding ramuscules of the ulnar ; from the elbow-joint. Placed beside the 

 B5, Branch forming the internal collateral radial artery, the median is, towards the 

 of the index; B6, Rudimentary branch lower third of the fore-arm, immediately 

 passing to the thumb ; C, Collateral given below the posterior border of the great pal- 

 off by the median; cl, c2, c3, c4, Colla- mar tendon; it afterwards passes through 

 terals furnished by the median and ulnar. the carpal sheath, giving a branch that 

 a, Palmar branch of the ulnar ; 6, Super- constitutes the internal palmar collaterals 

 facial branch giving off a filament to the of the thumb, and external of the index ; it 

 hypothenar, and a second that forms the finally forms three branches, the first of 

 superficial nervous arch ; 61, Deep branch which anastomoses with the ulnar, at the 

 passing to the muscles of the skin ; ra, Not surface of the palmar arch, and is lost on 

 anastomosing with the median ; ml, ?n2, an artery ; the other two, receiving a fila- 

 Anastomosing with the corresponding branch ment from the uluar at the origin of the 

 of the median ; the innermost passes to the digits, bifurcate to form the internal palmar 

 muscles of the thumb ; c, c, c, Collaterals collateral of the annularis, and collaterals of 

 furnished by the ulnar the medius and index. The second gives, 



in addition, a slender branch, that is lost 



in the internal and middle lobe of the large cushion of the paw. In fine, the median of 



