C E T A C E A. 



781 



The maxillary and palatial bones of the baleen, or 

 whalebone whales, form, on their interior surface, 

 two inclined planes, which are concave, but resemble 

 in some respects the roof of a house inverted. It is 

 to these bones that the blades or plates of baleen are 

 attached. They are widest at a point of the im- 

 mense mouth, which is nearer to the bottom of the 

 gape than to the snout ; and they diminish in size as 

 they approach both extremities. They are attached 

 to the bone by an elastic cartilaginous substance, not 

 differing much in consistence from that by which the 

 bones of the swimming- paw and the phalanges of the 

 fingers are united, and which perform their motions 

 rather by the flexibility of this cartilaginous substance 

 than by the motion of bone upon bone, which is 

 common among land animals. This is characteristic 

 of an aquatic joint, and in fact one of the best dis- 

 tinctions of a structural kind between land and water 

 mammalia. The extremities of the latter are not, 

 in the native element of the animals, props by means 

 of which they have to support the weight of their 

 bodies ; these are supported by the whole surface, 

 and thus the moveable member has nothing to sup- 

 port but its own weight ; and as that weight is very 

 little different from that of water, the member moves 

 very freely on its cartilaginous pedicle, and the same 

 motion is produced by a far less violent muscular 

 effort than is necessary in land animals. In this way 

 the aquatic tribes have an advantage; they having 

 only to move, while the land ones have to carry their 

 own weight at the same time. 



The laminse of the baleen or whalebone, have mo- 

 tion on those peduncles, but it is doubtful whether 

 this motion is voluntary. When the mouth is shut 

 the plates fall down upon the inclined planes of the 

 palate in an imbricated manner, and when the mouth 

 is opened, they hang down with their points touching 

 the tongue. 



The plates are parallel to each other, and have a 

 transverse direction with respect to the axis of the 

 body. Several hundred of lamiiue may be counted 

 on each side, and in the Greenland whale they often 

 exceed ten feet in length. They are fixed to the 

 bone by a kind of fleshy or ligamentous substance. 

 Each lamina presents on its internal side a layer of 

 horny fibres, growing from the horny plates, but less 

 fine and more divided than the plates from which 

 they proceed. These fibres extend between the 

 plates, and form a fringe or loose border on the lower 

 part, so that the whole palate is covered with fringes, 

 the lips of which rest upon the upper surface of the 

 tongue. 



This last organ is large in all the species, but it is 

 especially so in the whalebone whales, in which it is 

 popularly, and not inaptly, compared to a feather 

 bed. It consists partly of muscle and partly of fat ; 

 and it is a portion of the animal which their enemies 

 attempt to seize with great avidity. This vast tongue 

 is convex on the upper part, so that it applies to the 

 points of all the fibres of the whalebone; and it is 

 necessary to take both into consideration, in order 

 properly to understand the economy of this vast and 

 singular mouth. 



The plates of whalebone consist of an immense 

 number of fibres slightly soldered together, and 

 covered with an epidermis in the living animal ; but 

 whether this epidermis is endowed with sense either 

 of taste or of touch, is not ascertained; but it is not 

 very probable, neither is it likely, that the cartilagi- 



nous peduncules by which the plates are attached to 

 the roof of the mouth, are possessed of the same sen- 

 sibility as the bulbs which are at the roots of the 

 hairs of land animals. There is no question, however, 

 that the tongue is a sentient organ : and that through 

 its whole length it is enabled to distinguish between 

 substances that are fit for being conveyed to the 

 gullet, and those which require to be ejected between 

 the blades of whalebone. The sense which it has 

 cannot, however, be considered as quite analogous 

 to what we call the sense of tasting ; because the 

 substances which pass over it do so in the entire 

 state, and there is little taste in any entire animal, in 

 one sense of the word. 



The form of the tongue, and of the palate with its 

 pending plates and their fringes, gives a curious form 

 and appearance to the mouth of the whale when it is 

 open for feeding, and the animal generally swims with 

 it in this state. From the form both of the upper and 

 under part, the anterior part of the mouth, and as far 

 backwards as the place where the blades of whalebone 

 are longest, it presents a sort of funnel to the water, 

 only this funnel has a curved plane for its section. 

 The water enters in great quantity at the anterior 

 part, but it meets with resistance from the plates, and 

 also from the contraction made by the approach of 

 the tongue and palate towards each other. By this 

 means the small animals, which the water holds sus- 

 pended, get entangled among the fringes, as in a net, 

 and they are left behind, while the greater part of the 

 water, filtered of its eatable contents as it were, 

 escapes by the sides of the mouth towards the bottom 

 of the gape, where the plates of bone are shorter. 

 There is still some portion of the water that reaches 

 an opening of the gullet, but it does not enter into 

 that organ, and of course not into the windpipe, as no 

 animal which breathes the air can admit water into 

 its breathing apparatus. The water which reaches 

 the extreme part often, and the return of it by the 

 same passage, would intercept the current of food to 

 the throat, which, as it comes in small quantities, 

 must come regularly and frequently, is received into 

 membranous sacs adapted for the purpose, and situated 

 in the volume of the enormous head. 



These sacs are furnished with muscles, by means 

 of which the water is ejected when they become in- 

 conveniently distended ; the water thus ejected passes 

 at once into another reservoir or reservoirs, into 

 which the air passages from the lungs open by means 

 of valves rising upwards. When these reservoirs have 

 received the water, a strong expiration of air from 

 the lungs raises the valves, and blows the water up 

 in those jets, the appearance of which forms a curious 

 feature in the economy of these animals. The 

 feeding thus goes on constantly, and the small quan- 

 tity of water which is flowing toward the entrance of 

 the gullet, and delivering to that orifice the food with 

 which it is charged, gradually accumulates in the 

 lower sacs, without in the least interrupting the 

 breathing of the animal whose nostrils are all this 

 while above water. But when these lower sacs be- 

 come filled, the water passes into the reservoirs with 

 which the nostrils communicate, and is got rid of in 

 the manner it has been stated. 



The same valves which prevent the water which 

 is squeezed from the sacs into the reservoirs, from 

 entering the lungs by the breathing passages, equally 

 prevent the entrance of water into these organs by 

 the pressure from without, even when the animal 



