Description of a " White Fish," or « W/iite Wliak:' 609 



The contrast between the quantity of blood relatively to 

 the size of the animal in which it circulates, when whales 

 and land-birds are compared, is most noticeable, this 

 being, of all warm-blooded animals, at the maximum in 

 the former and at the minimum in the latter. There is 

 also a similar contrast in the power which they respec- 

 tively have of resisting submersion ; birds under this con- 

 dition perishing speedily, while cetaceans may remain 

 beneath the water many minutes, and occasionally, as we 

 are informed by trustworthy observers, for more than half 

 an hour. 



The whole quantity of blood in birds being very small, 

 the supply of oxygen which it contains is rapidly exhaust- 

 ed, — even after a few pulsations of the heart. In whales, 

 on the contrary, the amount of both kinds of blood is 

 relatively very large, and even the venous blood here, as in 

 most other animals, still contains some available oxygen. 

 The blood of these animals must consequently serve as 

 reservoirs of this essential element, from which the tissues 

 at large may draw. The animal which has relatively the 

 largest amount of blood, other things being the same, will 

 resist interrupted respiration the longest. 



To the condition mentioned above must doubtless be 

 added another, viz : a greater capacity on the part of 

 whales to carry on vital operations with blood, which, as 

 regards the supply of oxygen, is of an inferior quality. In 

 proof of this we have no facts from which to draw infer- 

 ences ; but if the condition just referred to does exist, it 

 does not in any way weaken the explanation offered with 

 regard to the large quantity of blood in whales. 



The lungs are very fleshy, not divided into lobes, and 

 are covered by a thick, strong layer of fibrous tissue 

 under the pleura. The trachea is about three inches in 

 length, an inch and three fourths in diameter, has seven 

 complete rings, of unequal breadth, and in some instances 



JOURNAL B. S. N. H. 7 7 



