426 Mr. J. Couch on the species of Whales 



provj of far more value than might arise from the price of the oil 

 it may produce. A measurement of the length, the preservation 

 of the bones of the jaws, with a note of the situation and form 

 of the teeth or whalebone, and also of the blowing-holes on the 

 top of the head — whether single or double, — with the situation 

 and shape of the hump or dorsal fin, and the presence or absence 

 of a series of longitudinal folds under the throat, will consider- 

 ably assist in determining the character of an uncertain species. 

 But as also in some instances it hais happened that even an 

 observing fisherman has been at a loss to decide whether the 

 creature he has seen at sea has been a whale or one of the larger 

 species of sharks (and more than one of the latter class has been 

 known to attain the size, with much of the shape, of a whale of 

 the middle order, so that the basking shark was long confounded 

 with the whales, even by naturalists), it is proper to remark, that 

 cetaceous animals or whales may be easily determined, even 

 when moving through the water, by being seen to have their 

 tails placed horizontally, or across the direction of their course ; 

 whereas the line of direction of the tail in all true fishes, as the 

 shark, is upright, or perpendicular to their course, and con- 

 sequently with a lateral, and not an elevating or depressing 

 motion. The circumstance of spouting water or vapour from 

 the head, is also a character of most of the species of whales. 

 Whales, in fact, are not to be classed with fishes ; for they give 

 suck to their young with milk drawn from teats, and draw air 

 through breathing-holes on the top of the head into real lungs, 

 spouting it out again through the same orifices, either in the 

 form of vapour, or with an accompanying rush of water ; and it 

 is an excellent fitting of parts to the necessities of the creature, 

 that this horizontal position of the tail is so well adapted to the 

 purpose of raising the head with a slight effort, and of again sink- 

 ing it below the surface. It is thus that the rolling motion is 

 obtained which is seen in almost all the whales, when they offer 

 themselves to an observer, but especially in the group of Dolphins. 

 It appears, also, that some of the larger whales possess a power 

 which enables them to sink in the water by an imperceptible ac- 

 tion, independent of the motion of the tail ; for a fisherman has 

 informed me that he has seen, and carefully noted, a large whale 

 very near his boat, which more than once threw itself on its back, 

 with its white belly uppermost ; and after lying in this position 

 for a time, it sank without apparent effort, deeper and deeper, for 

 several fathoms, until it was out of sight. The tlev. Mr. Scoresby, 

 who was a Greenland fisherman for several years, has, I believe, 

 noticed the same thing; and it is known that several diving birds 

 are able to keep themselves deeply immersed without apparent 

 effort, while swimming and seeking to escape observation, — a 



