APPENDIX. 549 



sides of the thorax, pass in between the ribs near 

 their articulation, and also behind the ligamentous 

 attachment of the ribs, and anastomose with each 

 other. The medulla spinalis is surrounded with a 

 net-work of arteries in the same manner, more 

 especially where it comes out from the brain, where 

 a thick substance is formed by their ramifications 

 and convolutions ; and these vessels most proba- 

 bly anastomose with those of the thorax. 



The subclavian artery in the Piked Whale, be- 

 fore it passes over the first rib, sends down into 

 the chest arteries which assist in forming the 

 plexus on the inside of the ribs ; I am not certain 

 but the internal mammary arteries contribute to 

 form the anterior part of this plexus. The mo- 

 tion of the blood in such must be very slow ; the 

 use of which we do not readily see. The descend- 

 ing aorta sends off the intercostals, which are very 

 large, and give branches to this plexus ; and when 

 it has reached the abdomen, it sends off, as in the 

 quadruped, the different branches to the viscera, 

 and the lumbar arteries, which are likewise very 

 large, for the supply of that vast mass of muscles 

 which moves the tail. 



In our examination of particular parts, the size 

 of which is generally regulated by that of the 

 whole animal, if we have been accustomed to see 

 them in those which are small or middle-sized, we 

 behold them with astonishment in animals so far 

 exceeding the common bulk as the Whale. Thus the 

 heart and aorta of the Spermaceti Whale appeared 

 prodigious, being too large to be contained in a 



v. II. p. II. 36 



