3 io 



BACKBONED ANIMALS, 



whales are either armed with conical teeth or plates of 

 fibrous matter called whalebone. The amount of blood 

 in the whale is enormous ; the aorta or great artery from 

 the heart being alone one foot across, and probably at 

 every pulsation of the great heart ten or fifteen gallons of 

 blood are thrown out, The cetaceans range in size from 



FlG. 335. Whits whala (Beluga catodon], a cetacean that has been carried 

 alive from America to England by steamer, covered with sea-weed and 

 dashed frequently with water. 



the porpoise, three to five feet long, to the rorqual, one 

 hundred and three feet in length. 



Toothed Whales (Delphinoidea). This group in- 

 cludes the dolphins, porpoises, white whales, etc. The 

 common dolphin has long, extended jaws armed with from 

 forty to forty-seven conical teeth, and a prominent dorsal 

 ridge or fin. The porpoises,* the orca,\ or killer, the 

 blackfish, or round-headed grampus, the white whale, Be- 

 luga (Fig, 335), sperm-whale, and narwhal are allies. 



* A friend of the author, in attempting to capture a herd of por- 

 poises, drove them into a creek, and the capture was about to commence, 

 when the porpoises rushed toward the boats, several leaping completely 

 over them, and thus reaching the sea. 



f The orca also preys upon the young cf the walrus. In trie 

 stomach of one have been found the remains of thirteen porpoises and 

 fourteen seals 



