OMNIVORA C ARNIVORA. 461 



umbilical branches, the internal iliac artery is apparently continued by the 

 internal pudic, which gives off the haemorrhoidal artery to supply the urinary 

 and genital organs of the region, and the rectum posteriorly, and finally the 

 cavernous arteries. 



The external iliac artery resembles in its distribution that of the ruminant. 



The anterior aorta is wanting, the brachial trunks arising from the common 

 aorta. The vertebral, dorsal, and subcostal arteries of the right side are given 

 off by a branch which itself appears to represent the superior cervical artery. 

 A branch from the subscapular artery is the analogue of the deep humeral in 

 the horse ; the rest of the circulation of the anterior limb is mostly like that 

 of the ruminant. 



The carotid arteries arise singly from the brachio-cephalic trunk ; They bre.ak 

 up like those of the horse. There is no cerebrospinal branch of the occipital 

 artery. The internal carotid enters the cranium by the foramen lacerum posti- 

 cum, and forms a rete mirabile, assisted by the ophthalmic. The basilar artery is 

 formed as in the ruminant. The external carotid extends to the maxillary hiatus, 

 where it breaks up — i.e., the internal maxillary artery is in thi.s animal con- 

 sidered as part of the carotid. The lingual artery is separate from the facial. 



The veins call for little remark. What we have said of tlie jugular and 

 saphenic veins of the ruminant is also applicable here. The superficial veins 

 in the hog are for the most part buried in an exceedingly thick layer of fat. 



The thoracic duct usually opens into the left jugular vein, near its termina- 

 tion. It sometimes divides anteriorly and reunites, forming a cavity which 

 receives the terminal lymph vessels. 



CARNIVORA. 



The heart in carnivora is extensively related with the sterniim, the apex being 

 directed backwards. In shape the organ is very bluntly ovoid. There are no 

 well-defined 6ronc/iia^ arteries, but several oesophageals proceeding direct from the 

 aorta, in the posterior mediastinum ; some of these give off bronchial branches. 



The coeliac axis divides into the three typical branches, but there is no dis- 

 tinct right and left division of the gastric artery. There is given off a 'pancre- 

 atico-duodenal branch from the hepatic which anastomoses with the great 

 mesenteric artery. Near the latter a vessel arises which divides, supplying the 

 diaphragm anteriorly and the sublumbar region posteriorly. 



The internal iliac arteries are somewhat separated from the external ones, the 

 umbilicals being given off from their common trunk. They divide into two 

 chief branches, which may be considered representatives of the internal pudic 

 and gluteal arteries of the horse; the first of these calls for no special comment, 

 the second passes through the great sciatic notch with the great sciatic nerve, 

 and becomes lost in the gluteal and femoral muscles, first giving off spinal 

 branches ; the coccyx is supplied by branches of the middle sacral artery. 



The branches of the external iliac artery present few deviations of importance. 

 The circumflex ilii comes direct from the aorta. The posterior tibial artery is 

 rudimentary, while the anterior one gives off a large tarsal branch, and descends 

 in the third intermetatarsal space, inclining backwards, and forming a plantar 

 arch underneath the flexor tendons ; from this arch are given off three diqilal 



