PROFESSOR 1IYRTL S ANATOMICAL NOTES. 



acid, will prove that the before-mentioned arterial branch ramifies 

 th rough the diploe, reaching as far as the parietal bone. I have, for 

 this reason, called it the Art. diploetica magna, and I consider it to be 

 an attempt of nature to reproduce, in man, the great diploetic artery 

 which some years ago I discovered in the large Edentata,* as a 

 branch of the very large occipital artery, and which, in these animals, 

 penetrates the very dense diploe of the bones of the cranium as far as 

 the lamina cribrosa of the ethmoid, when it escapes, and is lost, with 

 the olfactory nerves, in the mucous membrane of the nose. 



Even when, as is sometimes the case, this branch of the human 

 occipital artery passes right through the mastoid foramen, and actu- 

 ally reaches the dura mater, yet a comparison of the diameter of the 

 artery as it enters, with that of the artery as it makes its exit 

 through the foramen, will show a very striking difference in size ; 

 the artery, as it makes its appearance at the inner side of the mas- 

 toid foramen, not having half the diameter that it possessed on its 

 entrance into the foramen, and, even in these cases, it sends a very 

 considerable off-shoot to the diploe. 



LlGAMENTTTM TEEES. 



It is said in most works on anatomy, that this ligament serves to 

 conduct nutritive blood-vessels to the head and neck of the femur. 

 I venture to doubt this general assertion, on the strength of isolated 

 injections of the arteria obturatoria, under the pectineus muscle. 

 These injections have proved, that all the capillary vessels in the 

 ligamentum teres are, at the point where this latter is inserted into 

 the oval depression on the head of the femur, reflected back again into 

 veins, forming a large number of fine capillary loops, which form a 

 very interesting object. When a vertical section of this ligament is 

 made, no arterial vessel can be singled out, passing from the liga- 

 ment to the bony substance of the head of the femur ; but if 

 you inject the perforating artery, of which the nutritive artery of 

 the femur is a branch, you will obtain a very satisfactory micro- 

 scopical injection of the interior of the bone; and, in a vertical sec- 

 tion of the injected femur, one may trace the vessels to the very 

 insertion of the ligamentum teres itself, without finding a trace of 

 even the minutest branch passing into it. Further there is no 

 anastomosis between the vessels of the round ligament and those of 

 the medullary cavity, which must have been the case were the 

 blood-vessels of the former destined to nourish the frame- work of the 

 reticulated interior of the head of the femur. 



* Vide " Ueber das Gefassystem der Edentaten." Denkschriften der Kait 

 Acad. Wissenchaft. Wien. vol. vi. 1854. 



