CARNIVORA. 



OMNIVORA. 



523 



In the hog the cerebral convolutions are still fewer than in the ruminant, 

 Taut beyond this fact, the brain presents no important comparative features. 

 The superior mamillary division of the fifth nerve pursues a remarkably short 

 course in the orbital fossa. The pneumogastric nerve unites in the cervical 

 region with the sympathetic ; its oesophageal portions differ chiefly in the 

 superior branch being very much larger than the inferior. 



The nerves of the brachial plexus p-esent few deviations from the type, with 

 the exception of the median and cvMtal nerves. The former of these, below 

 the carpus, supplies the interosseous palmar muscles, and afterwards "divides 

 into four branches, one for each of the four digits ; those supplying the large 

 digits reach the central interdigital space. The cubital nerve bifurcates near 

 the trapezium, one branch running down the flexor tendons externally, to 

 supply the outer digit, the other gains the anterior aspect of the metacarpus, 

 and furnishes the dorsal nerves of the external digits. 



In the lumbo-sacral plexus we note that the musculo-ctiianeous nerve on 

 reaching the metatarsus trifurcates, thus forming the dorsal nerves of the 

 digits. The anterior tibial nerve passes down between the large metatarsal 

 bones, and communicates with the plantar nerves, the external of which 

 supplies the outer and partly the inner digits, the internal nerve being small. 



CAENIVORA. 



In the brain of camivora the nates are smaller than the testes, and the 

 olivary bodies well marked. The olfactory lobes are exceedingly weU deve- 

 loped, the sense of sraell attaining, perhaps, its maximrni of acuteness in these 

 animEils. The fourth ventricle is large and deep. 



A branch of the seventh nerve accompanies the duct of Steno to the facial 

 region. The pneumogastric and sympathetic trunks are inseparably united 

 in the cervical region. The recurrent nerves arise by two branches which 

 eupply sparingly the trachea and oesophagus, these' organs being also supplied 

 by the tracheo-oisophageal branch of the superior laryngeal nerve. The 

 oesophageal plexus of the pneumogastric is better marked th an in the horse. 

 The bronchial nerves are nimierous and large. 



In the dog, the nerves of the brachial plexus as far as the carpal region 

 resemble in the main those of the horse. The dorsal nerves of the digits are 

 supplied by a cutaneous branch of the radial nerve. The median nerve is 

 attached superiorly to the cubital Inferiorly it inclines to the inner aspect of 

 the Umb, and below the carpus it divides into six branches, one of which 

 crosses over to unifp wilh a branch of the cubital, and form the superfixjial 

 •palmar arch. The remaining p alma r branches supply aU the digits excepting 

 the fourth and part of the third. The cubital nerve divides into a dorsal and 

 a palmar branch ; the first running down the forearm and carpus externally 

 to supply the fourth digit ; the latter divides into eight branches, which, deep- 

 seated, supply all the digits excepting part of the index or first, a branch 

 passing across to the pollex, and forming what may be regarded as a deep 

 palmar arch. 



