DEVELOPMENT AND FUNCTION OF HEMAL NODES 383 



and subcutaneous nodes of bovines previously described are 

 always hemal and ne^'er lymphatic nodes and since the large 

 regional lymph nodes of these animals or the sheep, are prob- 

 ably ne\'er converted into hemal nodes, the above assumption 

 becomes still more impi-obable. Besides, if hemal nodes are 

 con\'erted lymph nodes and the latter converted hemal nodes as 

 claimed by Forgeot, Piltz, Retterer, v. Schumacher and Warthin 

 they should not only be found at the seats of predilection for 

 lym])h nodes, but the combined number of lymph and hemal 

 nodes should not materially exceed that of the normal number 

 of hanph nodes, unless it be assumed — which no one has done — 

 that additional lymph nodes are formed anew simultaneously, 

 to take the place of those converted into hemal nodes pari passu 

 with the conversion of lymph nodes into hemal nodes. 



It has not been shown that the true hemal nodes of bovines 

 and sheep become diseased when the lymph nodes do, and no 

 one has found a single carcass in which the place occupied so 

 frequently by scores of hemal nodes was taken by a correspond- 

 ing number of lymph nodes. The latter is, to be sure, a par- 

 ticularly pertinent consideration in view of v. Schumacher's 

 conclusions and statement that hemal nodes usually possess 

 lymphatics. Nevertheless, although y. Schumacher explicitly 

 stated that there are two kinds of lymph nodes those with and 

 those without hmiphatics, he apparently uses the terms hemo- 

 lymph nodes (Blutlymphdriisen) and lymph node synony- 

 mously. Piltz, on the contrary, held that the blood sinuses of 

 hemal nodes have no connection with the vascular system origi- 

 nally and that lymphatics only grow into hemal nodes after 

 the blood sinuses have become obliterated by the proliferation 

 of lymphocytes. 



From ^mbryological evidence in my hands since half a dec- 

 ade it seemed clear to me that hemal nodes are not in connec- 

 tion with the lymphatics in their early development and that 

 the sinuses that may form in them are not in connection with 

 l>anph vessels. Furthermore, from the numeii'ous observations 

 on the carcasses of sheep of all ages, of several scores of the new- 

 born lambs and of many foetuses it is evident that it is impos- 



