CETACEA 487 



the skin, and a number of pecularities in the respiratory system 

 which help them to remain for several minutes under water, and 

 to be active the whole time. They have lost a number of the usual 

 mammalian characters, such as hair (except for a few bristles 

 round the mouth), claws, pinnae, all the muscles and glands of 

 the skin, the scrotum, salivary glands, and the clavicle. The only 

 trace of the pelvic girdle and hind limb is a small bone representing 

 the ischium. The blue whale [BalcEuoptera musculus=B. sibhaldi), 

 which is the largest known animal, living or extinct, and may be 



Fig. 377. — The Killer Whale {Orca gladiator). — From Beddard, after True. 



as much as 100 feet long, has occurred in British waters, but most 

 of those commonly seen round our coasts are much smaller. 

 Such is the porpoise [Phoccena phoccBna=Ph. communis) four 

 to five feet long, which swims and gambols in schools following 

 the herring and other small fish, and is often seen from the shore. 



FERUNGULATA 



The last cohort, the Ferungulata, contains a number of orders 

 which, although now diverse, show distinct similarities in some 

 of the fossil forms. It includes the four orders formerly included 

 under the now abandoned name Ungulata, or hoofed animals, 

 several extinct and minor orders, and the Carnivora, with which 

 we will begin. 



CARNIVORA 



The typically flesh-eating animals are the nearest to the central 

 stock of the cohort, and through their ancestors the creodonts 



