x /:/,'.! /. t <i.\fillH-:ilA TIONS. 627 



if deprived of the branches from the rraninl amuses. The internal jugular arises at the 



>r foramen lacernm, ut u dilatation of the lateral sinus named the bullnu yen* 



jiti/ulan's. ami |,a.-M'> to the subclaviun vein. Lastly, the )n>fttrinr jiujnlnr (or vertebral 



iMLtt.d li'-nr.itli tl.e irn:i t complrxus, and in relation with the cervical vertebra, 



c- urii - tli,- hlood from the spinal sinuses in this region, ami \vhi<-h, in Silipcds, is received 



l<\ the oedpital and vertebral veins. 



The in ft rior vena cava corresponds to the pwterior vena cava of animals, and receiv. > 

 tin- blood from all the subdiaphragmatic veins. It originates from the union of the 

 t\\ cumin.,,, il.'nc vein*, at the third lumbar articulation, ami terminates in the rijjht 

 uuriele. In its course it receives the median sacral, lutnlxir, renal, suprarenal, inferior 

 fihn ni'-. and right tpermalic reins. The latter forms on the surface of the testicle, and at 

 the origin of the cord, a rich network the tpermatic plerus ; on the abdominal portion of 

 the cord it c. 'ii-titut. s tin- ptimjiiiiijorni j>l''jcus. 



The vena cava also receives the vena porttv, which has the same disposition as in 

 animals. It begins by three branches : the great and situ ill mesaraic and splenic veins. 

 For affluents, it has the pancreatic and duodenal v, nnlo, and the ri^ht gastro-omental 

 vein. It passes behind the pancreas, and not through that gland, as in the Horse. 



The veins of the abdominal limb are divided into deep and superficial. The first 

 terminate hy forming the femoral vein, which, in joining il.e vessels of the pelvis, 

 constitutes the common iliac vein. The fuperjicial veins commence by a network on 

 the dorsum of the foot, which gives origin to the two saphenas : external and internal 



FOURTH SECTION. 

 THE LYMPHATICS. 



CHAPTER I. 



GENERAL CONSIDERATIONS. 



CHARGED with the absorption and transport of the chyle and lymph, the 

 ///)/)/;//< or absorbent vessels are convergent canals with thin and transparent 

 walls, which originate in the texture of organs by tine reticulated radiculte ; 

 and which, after traversing one or more ganglia (or glands) glandiform 

 tidies j-lai-t '1 on their course enter the venous system by two trunks : the 

 tli"i-!n-i<- <lint ;iud the great lymphatic o///. 



LYMPHATIC VESSELS. 



These canals resemble veins in so many points, as to merit the name of 

 ood veins. Like these vessels, the lymphatics arc dim-ted from the 

 periphery to the < ntn: of the circulatory apparatus ; like them, they are 

 imdulatcd cylindrical tubes ; internally, and at those points where they 

 outwardly ap]>ear to be constricted, they show numerous valves which look 

 towards the heart ; like the veins, again, they separate into two orders of 

 canals: the ones deep-seated, lodged in the vasculo-nervoiis intenmiscular 

 sleuths; the others superficial, situated on the surface of containing apon- 

 euroses ; like the veins, also, the lymphatics terminate in two principal trucks 

 resembling the vente cuvac ; and, finally, as the veins have three- tunics, so 

 huve the lyinphuties, these not dilVi-ring in any r< speet. except in being \, i y 

 iniieli thinner. 



In currying this parallel still farther, wo will find other analogies whoso 



was but little susprcti (1 until n emtly : the glands those organs 



which are apparently glandular, and seem to IK) proper to the lymphatic 



m are tliev i\l ivpir-.-nt. d in tin vmous svsU-ni by the liver 



2 8 2 



