486 PHYSIOLOGICAL BBRH& 



D. 744. The brain and the upper part of the spinal cord of a Lion 

 (Felis ho) with the arteries injected. 



In this beautiful preparation, the origin of the chief 

 arteries of the hrain and a great part of their distribution 

 are clearly shown. The essential points of the arterial 

 arrangement arc oinparable to the condition found in Man. 

 Anterior, middle, and posterior cerebral arteries can be dis- 

 tinguished arising in much the usual places from the circle 

 of Willis. Upon the right side the posterior cerebral 

 artery consists of two separate trunks. 



The superior cerebellar artery arises by two roots on the 

 left side, one from the basilar artery, the other from the 

 posterior arm of the circle of Willis. 



The anterior (ventral) and inferior (posterior) cerebellar 

 arteries form branches of a common trunk. 



The lateral parts of the circle of Willis arc very strongly 

 developed. 0. C. 1326. 



lluntcrhin. 



D. 745. The brain of a Sheep (Ovis aries) with the arteries in. 

 jected. In this specimen the origin of the anterior and 

 middle cerebral arteries from the circle of Willis is more 

 plainly visible than in the preceding specimen. The posterior 

 cerebral and superior cerebellar arteries are represented by 

 a number of small vessels that arise from the hinder part 

 of the circle of Willis and from the anterior end of the 

 basilar artery. The lateral parts of the circle of Willi- are 

 remarkably stout, as in the Lion (D. 744). Bristles have 

 been inserted into the various cranial nerves. 0. C. 1327. 



I Iunt< rtiui. 



D. 746. The brain and the upper part of the spinal cord of a 

 Porpoise (Phocccna phocama), injected. 0. 0. 1'.\:\'2. 



Hunterian. 



D. 747. The basilar artery of a Rorqual (Balcenoptera sp.). 



O.C.939na. 



D. 748. The main arteries of the human hrain, injected, isolated, 

 and -pread out on a flat <url'ace. The anterior communi- 

 cating artery i- abnormally Inn- and -lender. 



