3878 The Zoologist — Febkuary, 1874. 



fishes in the sea : were it reversed he would not long maintain his 

 amphibious existence. 



Well then, as to the action of swimming, how is this performed ? 

 partially by his paddles and partially also by the movements of 

 his spinal column. I am told, — and I believe it notwithstanding 

 the danger of accepting any "I am told" in Natural History, — 

 that whales and porpoises invariably move the vertebral column 

 vertically — that is, upwards and downwards ; now it is well known 

 that fishes move the spinal column from side to side or horizontally; 

 this may be seen every day in an aquarium. Seals adopt the plan 

 of fishes, and swing their vertebral column and posterior extremities 

 from side to side. I never cease to regret having missed the oppor- 

 tunity of seeing the porpoises at Brighton : it may not occur again : 

 then indeed I might have witnessed and verified that vertical action 

 which now I am obliged to take for granted. It must be admitted 

 that the structure of a porpoise entirely favours this conclusion, but 

 how often are conclusions from structure erroneous, because we 

 mistake the meaning of the structure. 



Turtle. — The action of a turtle in the water is very beautiful ; 

 his anterior paddles move slowly, sedately, and simultaneously, like 

 the wings of a rook reluming at eventide from its wearisome and 

 monotonous labour of delving in the earth for wireworms : faithful 

 slave of man, it receives a slave's reward. 



Mackerel. — A word on mackerel: our friends at Brighton have 

 succeeded iu keeping mackerel alive for weeks — a great triumph, 

 but, alas ! the result is disappointing : the mackerel is of all fishes 

 the least graceful, the least easy in its movements : possessing a 

 form the very model of symmetry, it nevertheless swims with diffi- 

 culty and apparent timidity, just as a human being afilicled with 

 lumbago is reluctant to move a muscle from a dread of the conse- 

 quences. 



The Sleep of Fishes. — How often has the enquiry been made, 

 Do fishes sleep ? and how futile and unsatisfactory have been the 

 answers; 1 suppose scarcely any one recollects a clear and decided 

 solution. The question may be extended and enlarged, and fishes, 

 with regard to the act of taking rest in sleep, may be divided into 

 diurnal and nocturnal, a division which I may state, with some 

 degree of confidence, has never been worked out. Before you can 

 answer the simple question. Do fishes sleep ? you must of necessity 

 inform yourself of the habits of the fish you would place in the 



