44 PHYSETERIDA. 
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. Il. Physeteridze. 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 vertebre 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. 
