The Zoologist— August, 1873. 3635 



has continued to do so ever since. The later arrival was, at first, 

 less sociably inclined ; but both have latterly become equally tame, 

 and frequently, while receiving fish from my hand with the gentle- 

 ness of pet dogs, have permitted me to pat and stroke their slippery 

 india-rubber-like backs. During feeding-time it is amusing to watch 

 the avidity with which these porpoises take their food ; one, the 

 more active of the two, usually securing the lion's share, and dis- 

 playing marked sagacity by frequently snatching a second or third 

 morsel before disposing of the first. The keeper in charge of these 

 interesting animals is now in the habit of summoning them to their 

 meals by the call of a whistle ; his approaching footsteps, even, 

 cause great excitement in their movements, and recent experiments 

 have proved them to be acutely sensitive to the vibrations of sound. 

 By the physiologist a more pleasing spectacle can scarcely be 

 witnessed than the graceful actions of these Cetacea, as they 

 swiftly pursue their course up and down their spacious tank, 

 ascending to the surface of the water at intervals of fifteen or 

 twenty seconds, to breathe, each inspiration being accompanied 

 by a spasmodic sob-like sound, produced by the rush of air as a 

 breath is rapidly liberated and inspired through the single central 

 blow-hole. Onward progress is effected in these animals, as in all 

 other Cetacea, exclusively by the action of the horizontal caudal 

 fin ; the development of muscle at the "wrist" of the tail on which 

 this action depends being enormous and plainly visible externally ; 

 the pectorals are devoted principally to the jiurpose of steering the 

 creature to the right or left, aiding it also in rising to the surface 

 of the water. The fact alone of the porpoise suckling and evincing 

 much maternal solicitude for the welfare of its young indicates the 

 superiority of its position in the zoological scale above that of the 

 other representatives of the finny tribe; and to this, in addition to 

 the remarks just made upon their sagacity when feeding, many 

 other facts may be cited, pointing in the same direction. The 

 curiosity attributed to these creatures, as illustrated by the expe- 

 riences of Mr. Mattieu Williams, receives ample confirmation from 

 their habits in confinement. A new arrival is at once subjected to 

 the most importunate attention, and, advancing from familiarity to 

 contempt, if disapproved of, soon becomes the object of attack and 

 persecution. A few dog-fish {Acauthins and Muslelus), three or 

 four feet long, placed in the same tank, soon fell victims to their 

 tyranny, the porpoises seizing them by their tails, and swimming 



