702 THE VEINS. 



"1. By somewhat lar2;e ascending branches from the posterior part of the 

 podophyllous and solar plexuses. 



" 2. By the deep internal venous apparatus of the third phalanx. 



" 3. By the deep veins arising from the coronary bone and the ligaments 

 and tendons surrounding it. 



" The ascending branches of the podophyllous tissue are introduced by the 

 numerous foramina which traverse the base of the cartilaginous plate and the 

 inferior fibrous covering of the plantar cushion ; they follow the canals which 

 continue those foramina in the substance of the cartilage, and reach its internal 

 face, along with the branches proceeding from the intra-osseous venous system 

 and those coming from the tendons and ligaments, forming a fasciculus of five 

 or six thick converging veins which unite in two large ascending branches. 

 These anastomose with each other before their definitive junction with the two 

 peripheral branches resulting from the superficial cartilaginous plexus, with 

 which they concur in constituting the digital vein." 



b. Internal or Intra-osseous Venous Apparatus. 



" Girard, junior, and Rigot have denied that the plantar artery had, in the 

 interior of the phalanx, a satellite venous system. These two able anatomists 

 committed an error. 



" The disposition of the venous apparatus in the interior of the phalanx is 

 absolutely identical with that of the arterial. 



" The satellite radicular venules of the terminal arteries converge, by forming 

 successive anastomoses, towards the semilunar sinus, into which they enter by 

 the anterior interosseous canals, ascending and descending, and by which the 

 emergent arteries from the semilunar anastomosis pass outwards. There they 

 join into a semicircular canal, the satellite of that anastomosis, which is con- 

 tinued backwards by two efferent veins that follow the posterior canals of the 

 semilunar sinus, emerge by the plantar foramina, pass into the fissure of the 

 same name, ascend within the basilar process, lie at the internal face of 

 the cartilaginous plate, in one of the infractuosities with which it is sculptured, 

 and concur in the formation of the deep layer of the cartilaginous plexus. 



" Beside these veins converging towards the cartilaginous plexus, there is 

 a small number of divergent ones which follow^ the track of the arteries, and 

 pass into the podopliyllous plexus through the anterior porosities of the phalanx. 



" The dissection of specimens injected by the veins puts this arrangement of 

 the venous apparatus in the interior of the os pedis beyond a doubt. 



" But is this internal venous system limited to the group of vessels which 

 are satellites of the arteries, or is it not rather extended over a vaster surface, 

 and may not all the areolae of the spongy tissue of the bone be considered as a 

 dependency of it ? 



" This way of viewing it would seem to be supported by the result of certain 

 injections, in which the material introduced by the neighbouring veins has filled 

 all the internal spongioid of the bony tissue ; though this was probably due to 

 an accident in the operation, and it is presumable that the direct passage of the 

 venous injection into the areola; of the spongy tissue arose from a rupture in the 

 vascular walls. If the tissue of the phalanx formed a kind of diverticulum for 

 the venous system, as the opinion just given would admit, operations performed 

 on this part during life, when the texture of the bone is deeply involved, ought 



