MUSCLES OF THE TRUNK. 



245 



arch where it forms adhesions. It has been described, in human anatomy 

 s& the fascia tramversahs. ''' 



Action.— li compresses the abdominal viscera when it contracts, and 

 presses them against the vertebral column. 



DIPFBEENTIAL OHAEACTEES ' ^'g- 117. 



OP THE MUSCLES OF THE 

 ABDOMINAL KEGION IN 

 OTHER THAN SOLIPED 

 ANIMALS. 



As has been alreaiJy 

 said, the development of the 

 abdominal tunic is in pro- 

 portion to the volume of 

 the digestive viscera. This 

 membrane is, therefore, 

 very wide and thicli in 

 Ruminants, while it is re- 

 duced to an insignificant 

 leaf in the Pig and Car- 

 nivora. In these animals 

 the internal crural aponeu- 

 rosis does not exist, and 

 is replaced by a cellulur 

 layer. The aponeurosis of 

 the great oblique, instead of 

 being doubled into two 

 lamiuse at its posterior 

 border, is entirely reflected 

 to form the crural, arch, 

 In the latter animals, the 

 great oblique is also dis- 

 tinguished by the extensive 

 development of its mus- 

 cular part, and the narrow- 

 ness of its aponeui'osis. 



The muscular portion 

 of the small oblique of Ru- 

 minants occupies the entire 

 space comprised between 

 the posterior border of the 

 last rib, the extremity of muscles of the anteeioe aspect op the body op man; 

 the transverse processes of on the left side the superficial layer is seen, on 

 the lumbar vertebrae, and The eight the deeper layer. 



the external angle of the l, Pectoralis major ; 2, Deltoid ; 3, Anterior boraer of the 

 ilium. The small retractor latissimus dorsi ; 4, Serratus magnus ; 5, Subclavius, right 

 side ; 6, Pectoralis minor ; 7, Coraco-brachialis ; 8, Biceps, 

 with its two heads ; 9, Coracoid process of the scapula ; 10, 



of the last rib is not distinct 

 from the principal muscle. 

 This arrangement is like- 

 wise present in the smaller 

 domesticated animals. It 

 is also to be remarked that, 

 inRwminants, the tendinous 

 intersections of the great 

 rectus muscle of the aibdomen 

 are more marked at its 

 superior than its inferior face ; and that the aponeurosis of the transverse is much thicker 

 and more resisting than in Solipeds. 



COMPARISON op THE ABDOMINAL MUSCLES OP MAN WITH THOSE OP ANIMALS. 



With the exception of some slight differences, the abdominal muscles of Man present 

 the same disposition as those of the smaller animals. 



The abdominal tunic is not present, but is replaced by a cellular layer which 



19 . 



Serratus magnus, right side; 11, External intercostal muscle 

 of the fifth intercostal space ; 12, External oblique ; 13, Its 

 aponeurosis with the linea alba ; 14, Poupart's ligament ; 

 15, External abdominal ring; '16, Rectus muscle of right 

 side; 17, Pyramidalis muscle; 18, Internal oblique; 19, 

 Conjoined tendon of internal oblique muscle and Poupart's 

 ligament. 



