196 



Cetacea.- 



-JI.\JIMALIA.- 



-Cetacea. 



stomach, neither is there any inter-communicating 

 channel common to the three first cavities, bj' which 

 the aforesaid function could be mamtained. In the 

 accompanying figure A represents the oesophagus, b, c, 

 D, and B tlie four stomachal compartments, f tlie 

 diiodenimi. The only approach to any unusual exten- 

 sion of the internal secreting membrane, is such as 

 is gained by the presence of numerous rugiE or foldings, 

 which are more or less irregularly disposed throughout 

 the entire compartments. Of the other circumstances 

 in connection with the aUmentary canal which call for 

 particular attention, are those which refer to the great 

 length of the intestinal tube, and to the presence or 

 absence of a coecum. Most of the spouting whales 



Fig 78. 



Compound stomach of the ^Vhite Whale (Beluga CatodouJ. 



have no coeciim, but this appendage is present in 

 the mysticete and in tlie piked whale. The chylo- 

 poietic viscera exliibit several pecuharities of form 

 which need not be dwelt upon ; but we may remark, 

 in passing, tlie entire absence of any gall-bladder 

 in tlie zoophagous species, whilst it is present in 

 the herbivorous forms. The reproductive organs are 

 largely developed, the mammje of the female being 

 placed in the inguinal region in the true whales and 

 dolpliins, and in the pectoral region in the phytopha- 

 gous manatees and dugongs. The circulatory system 

 has already, in part, engaged our attention, but the 

 contemplation of such a marvellous machinery in these 

 bulky creatures deserves some fiirther comment. The 

 amount of muscidar pressure required to propel the life 

 stream from the volimiinous cavities of the heart of a 

 rorqual is something well calculated to excite the 

 astonishment of any one possessing the slightest ac- 

 quaintance with the principles of hydraulic power. 

 The main arterial trunk of tlie spermaceti whale has a 

 circumferential measurement of at least three feet, "and 

 when," says the illustrious John Hunter, " we consider 

 these as applied to tlie cu'culation, and figure to our- 

 selves that probably ten or fifteen gallons of blood are 



thrown out at one stroke, and move with an immense 

 velocity tlirough a tube of a foot diameter, the whole 

 idea fills the mind with wonder." Generally speaking, 

 the form of the heart is precisely similar to that of 

 other mammals, but m the phytophagous dugong the 

 apex of the heart is deeply cleft, so that tlie ventricles 

 are partly detached from one another. In regard to 

 the venous system, it should also be noted that its 

 arrangements, in some parts, are even more plexiforni 

 than obtains in tlie arteries. This is particularly seen 

 in the branches of the great anterior vena cava, and 

 more especially in the veins which surround the spinal 

 cord; whilst another stiU more interesting pocuharitj- 

 connected with this system, is, that scarcely any of the 

 veins are furnished with valves intemalty. 

 AH these conditions are admirably adapted to 

 the suboceanio habits of the cetaceans, and 

 taken in connection with otlier stnictures yet to 

 be described, manifestly indicate evidences ot 

 harmonious design. We allude here principally 

 to tlie character of the dermal and subcutaneous 

 investment of the body. This consists essen- 

 tiall}' of the same elements which enter into the 

 composition of the hide of ordinary quadnipeds ; 

 but nearly all trace of hares or bristles have 

 disappeared in tlie zoophagous species, these 

 stractures being represented only m the embry- 

 ijiiic condition of dolphins and in adult whales, 

 by a few -bristles attached to the anterior part 

 of the upper or lower jaws. In some species 

 the cuticle is rather thin, but in others it 

 attains a remarkable development, and we have 

 observed it to be upwards of an inch in thick- 

 ness in the great rorqual. In hke manner the 

 corium acquires remarkable density andstrength, 

 passing gradually into a fatly tissue, which is 

 commonly called the blubber, and wliich varies 

 in quantity in different species, being in some 

 found only a few inches thick, and in otliers 

 surrounding the muscles to the depth of a foot and 

 a half or even two feet below the cuticular smface. 

 The larger kinds of whale are capable of yielding 

 upwards of twenty tons of oil, and as tlie oil is 

 worth about £30 per ton, the " whale fishery," as 

 it is en'oneously tenned, proves a very lucrative 

 trade. Upwards of twentj' thousand tons are annually 

 brought to this country by British whalers, notwith- 

 standing the Americans and other nations have vastly 

 increased the competition of late ypars. "In 1821," 

 says the late Professor Edward Forbes, " the British 

 whale fishery employed one hundred and fifty-nine 

 ships, but the decline of the nortlicru fisheries has 

 reduced tlieir number to the half. We are compen- 

 sated for this, however, in the energy and success witli 

 which our Australian colonies are joining in the busi- 

 ness; and the rich source of blubbery wealth which 

 the nortli once was, the south now promises to be. At 

 present we are beaten in whaling by our American 

 cousins ; but the great advantages presented by the 

 proximity of Australia and the Aucldand Isles to the 

 southern whaling gi'ounds, are giving us a fresh start, of 

 which we will not be slow to avail om'selvcs. In 1844 

 the American whaling fleet numbered no fewer than 



