44 



PHYSETERID^F. 



whale, and is, therefore, composed of the refuse matter of the cepha- 

 lopods that form its food." Squids, cuttlefish, and octopi, large and 

 small, are eaten by the Sperm Whale, and the largest octopus that 

 ever lived, armed with its formidable beak, and long, disk-covered 

 arms, would be helpless when seized by the enormous jaws of this 

 mammal. The Sperm Whale goes in herds, at times of hundreds of 

 individuals, usually led by some old bulls. It has been known to 

 remain below after diving for more than an hour at a time, and it 

 requires about ten minutes to oxidize the blood after rising to the 

 surface, the animal respiring in that period about seventy times. 

 When alarmed, the Cachalot usually sinks at once, but occasionally 

 it will raise half of the body out of the water in the effort to see its 

 enemy. Hunting this whale is not without danger, and many a boat 

 and its crew have been destroyed by a blow from the tremendous 

 flukes. 



Fam. II. Physeteridse. Sperm Whales. 



Upper jaw without functional teeth, those in the mandible 

 various, number often reduced. Pterygoids meeting on the median 

 line and hollowed on outer side. Transverse processes of the arches 



FIG. 11. PHYSETER MACROCEPHALUS LOWER JAW. 



No. 296 Field Columbian Mus. Coll. 



of dorsal vertebrae cease near end of the series and are replaced at a 

 lower level by processes on the body. Costal cartilages not ossified. 

 Cranium elevated into a prominent crest behind the nares, and 

 asymmetrical around narial openings. 



