Popular IBtcttflitarg of gmmatrtr Mature. 735 



they have warm blood, a complete double 

 circulation ; they breathe the atmosphere 

 by means of true lungs ; and their reproduc- 

 tion and the nourishment of their offspring 

 associate them with the true mammiferous 



Mr. Bell then proceeds to say, that "the 

 general form of the Cetacea is similar to that 

 of fishes, in the horizontal elongation of the 

 body, the rounded and smooth surface, the 

 gradual attenuation of the extremities of 

 the trunk, and the development of fins and 

 especially of the tail as means of progres- 

 sion. The arrangement of the bones com- 

 posing the anterior limb is one of the most 

 important and curious parts of this subject. 

 The whole of the fin consists of exactly the 

 same elements as those which compose the 

 arm and hand of man ; but so concealed 

 underneath the thick skin which envelopes 

 it, that not a trace of these bones is to be seen 

 externally. In this respect an intermediate 

 structure is exhibited by the anterior extre- 

 mities in the Seals." 



" The posterior extremity is, in the whole 

 order, either absolutely wanting, or merely 

 rudimentary. In the latter case, its only 

 vestige consists of certain small bones, the 

 imperfect representative of a pelvis, sus- 

 pended, as it were, in the flesh, and having 

 no connexion with the spinal column. In 

 this respect a striking difference is observed 

 between these animals and the Seals : in the 

 latter, the posterior extremities are carried 

 backwards, and perform the office of a true 

 caudal fin ; but in the Whales, this most im- 

 portant organ of progression consists of an 

 extremely broad and powerful horizontal 

 disc, varying in figure in the different genera, 

 but in all constituting the principal instru- 

 ment of locomotion. This extraordinary 

 organ is not placed vertically as in fishes, 

 but horizontally ; and the admirable adapt- 

 ation of such a peculiarity in its position to 

 the requirements of the animal forms a fresh 

 and beautiful illustration of the perfection 

 of Creative Wisdom. The fishes, respiring 

 only the air contained in the dense medium 

 in which they live, do not require any access 

 to the atmosphere ; and their progression 

 therefore is principally confined to the same 

 place : but the Whales, breathing the atmo- 



r"iere, are necessitated to come to the surface 

 each respiration, and hence require an 

 oar of inconceivable power, the position of 

 which applies its impulse in a vertical di- 

 rection, so as to impel their ponderous bodies 

 from the lowest depths of the ocean to the 

 surface, every time the lungs require to be 

 replenished with fresh air. The greatest 

 rapidity of motion is produced by alternate 

 strokes of the tail against the water, upwards 

 and downwards ; but their more ordinary 

 progression is effected by an oblique lateral 

 and downward impulse, first on one side and 

 then on the other, as a boat is impelled for- 

 wards by a single oar in the act of sculling. 

 The extent of the tail in some of the larger 

 species is enormous ; its superficies being no 

 less than about a hundred square feet, and 

 its breadth considerably upwards of twenty 

 feet." 

 The respiration of these animals is another 



w itn tne unmncmng nrmness OT a master 

 ind, relying upon philosophical principles, 

 id not yielding to popular prejudice by 

 tiling that a fish which he knew to be a 



important part of their physiology. It ap- 

 pears that often, when the blow-holes are 

 far out of the water, a jet of water of con- 

 siderable size is thrown up with great force 

 and to a considerable height ; a circum- 

 stance which can only be accounted for by 

 supposing that the water taken into the 

 mouth, and carried back into the pharynx, 

 is then regurgitated by the blow-holes. 

 " Let us suppose," says Cuvier, " the Cetacea 

 to have taken into its mouth some water 

 which it wishes to eject. It moves its tongue 

 and jaws as if it were about to swallow it ; 

 but, closing the pharynx, it forces the water 

 to mount into the nasal passages, where its 

 progress is accelerated by annular muscular 

 fibres, until it raises the valve (between the 

 nasal passage and two pouches or reservoirs) 

 and distends the membranous pouches above. 

 The water once received into these pouches 

 can be retained there until the animal wishes 

 to spout. For that purpose it closes the valve 

 to prevent the descent of the water again 

 into the nasal passages below ; and forcibly 

 compresses the pouches by means of the 

 fleshy expansions which cover them : thus 

 compelled to escape by the narrow crescentic 

 aperture or blow-hole, it is projected to a 

 height corresponding with the force of the 

 pressure." 



With the unflinching firmness of a master 

 min* -- ' 

 and 

 calli _ 



mammiferous animal, Linnaeus separated 

 these cetaceans from the fishes, and associated 

 them with the mammalia, on account of 

 their warm bilocular heart, their lungs, their 

 movable eyelids, their viviparous generation, 

 the teats by means of which they suckle 

 their young, and the other details of their 

 anatomy which he, Cuvier, and all succeed- 

 ing naturalists of note, allow to sufficiently 

 distinguish them. 



The Cetaceans are divided by Cuvier into 

 two great tribes or families, one of which he 

 terms Herbivorous Cetacea; the other, Or- 

 dinary Cetacea. And M. F. Cuvier thus ar- 

 ranges the order : Tribe 1. PHYTOPIIAGA. 

 These are characterized by having teeth of 

 different kinds ; the molars with flattened 

 crowns, corresponding to the vegetable na- 

 ture of their food. Mamma; two, pectoral. 

 Lips provided with stiff bristles. External 

 nostrils two, situated at the extremity or 

 upper part of the rostrum, which is obtuse. 

 Genera : Manatus, Cuv. ; Halieore, Cuv. ; 

 Rytina, 111. Tribe 2. ZOOPHAGA. Teeth of 

 one kind or wanting, not adapted for masti- 

 cation. Mamma; two, pudendal. External 

 nostrils double or single, situated on the top 

 of the head. And he further divides them 

 into 1. Those which have the head of mo- 

 derate size : family Delphinidce ; charac- 

 terized by having teeth in both jaws, all of 

 simple structure, and, generally, conical 

 form : and 2. Those with the head of im- 

 moderate size, equalling one-third the length 

 of the body; forming two families,!. Cato- 

 dontidce ; with numerous conical teeth in the 

 lower jaw, and blow-holes confluent. 2. Ba- 

 Icenidce ; which have no teeth, but their place 

 supplied by the plates of baleen or whale- 



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