CETACEA. 589 



ihe tympanum, which, in the Porpoise, is out,) that they are not described by him with 



only by contact, but in others by a bony the same minuteness and detail as the cochlea 



union; the other attachment is formed by the and other parts of the organ. It may also be 



tendon, above described, being united to the observed that the more extensive researches of 



inner surface of the membrana tympani. Its Hunter preserved him from the error into which 



base articulates with the incus. Cuvier has fallen of ascribing to the Cetacea a 



" The incus is attached by a small process to structure of the cochlea which is peculiar to a 



the tympanum, and is suspended between the small part only of the order. The depression 



malleus and stapes. The process by which it of the gyrations of the cochlea to nearly the 



articulates with the stapes is bent towards that same plane, and their limitation to one and a 



bone. half in number, is certainly not applicable to 



" The stapes stands on the vestibulum, by a the DelphinidtEj and it may be doubted how 



broad oval base. In many of this tribe, the far it can be with accuracy asserted of the 



opening from side to side of the stapes is so Balance.* 



small as hardly to give the idea of a stirrup. The canals which establish a communicatioa 



" The muscles which move these bones are between the labyrinth and the interior of tine 



two in number, and tolerably strong. One cranium, viz. the aqueductus vestibuli and 



arises from that projecting part of the tym- aqueductus cochleae, are very large in the Del- 



panum which goes to form the Eustachian phinida, especially the latter.] 



tube, and running backwards is inserted into a Taste. This sense probably exists in the 



small depression on the anterior part of the Herbivorous Cetaceans, whose tongue, although 



malleus. The use of this muscle seems to be but slightly moveable, has notwithstanding . 



to tighten the membrana tympani ; but in those complicated and delicate structure. But has 



which have the malleus anchylosed with the this sense a special organ in the Spouting Ce- 



tympanum, we can hardly conjecture its use. taceans ? Some doubts may be allowed to 



The other (o) has its origin from the inner surface exist on this subject. The tongue of the Dol- 



of the tympanum, and passing backwards is phin and that of the Porpoise have neither 



inserted into the stapes by a tendon, in which fossulate papillae nor conical papillae ; they only 



I found a bone in the large Bottle-nose. This present on their surface slight elevations, of 



jnuscle gives the stapes a lateral motion. What which the middle appears to be perforated, and 



particular use in hearing may be produced by their edges are fringed, as if for multiplying 



the action of these muscles I will not pretend the sensations of touch. 



to say ; but we must suppose whatever motion Touch. The general organ of touch, the 



is given to the bones must terminate in the skin, has formed, in the Spouting Cetaceans, 



movement of the stapes. the subject of important researches, which have 



" The immediate organ of hearing is contained given a more extended knowledge of this organ 



in a round bony process, and consists of the in general than was before possessed, 



cochlea and semicircular canals, which some- According to the observations of MM. 



what resemble the quadruped ; but besides the Breschet and Roussel de Vauzeme, there may 



two spiral turns of the cochlea, there is a third, be distinguished in the skin of the Cetaceans, 



which makes a ridge within that continued as in that of other Mammals, six principal 



from the foramen rotundum and follows the constituents which either penetrate or are 



turns of the canal. superimposed on ofce another, but which are 



" The cochlea (/c, Jig. 276) is much larger severally destined to fulfil a special function, 



when compared with the semicircular canals, 1. The derm or cor'mm (lederme), a dense 



than in the human species and quadruped.' 7 fibrous cellular texture, which contains and 



Besides its greater relative size, the coch- protects all the other parts of the skin. In 



lea of the Delphinid<e differs from that of the Whale it is constantly white and opake, 



the human subject in the greater pro- and its peripheral surface presents a series of 



portional extent, and especially the form and papillae, the intervals of which are occupied 



disposition of the scala vestibuli, which, in- by the epidermis, which forms for each a 



stead of being one compartment of a single sheath. 



tube divided in the direction of its axis, is a 2. The papillary bodies { les corps papil- 



complete conical tube. It also forms an oblique laires) consist of papillae covered by the derm, 



sigmoid curve before commencing its spiral They have a nacrous lustre, and are several 



turns, which are two and a half in number. lines in length in the Whale, but are much 



The semicircular canals have the same dis- shorter in the common Dolphin and Porpesse. 



position as in Mammalia, but are relatively These papillae are composed of fibres pene- 



smaller. trated by vessels ; they originate from the sub- 



Cuvier, in correcting the error into which cutaneous nervous plexus and return back again 

 Camper had fallen when lie denied the to the same ; the derm serves merely as a 

 existence of the semicircular canals in the sheath to the papillae, the extremities of which 

 Whale, appears to have overlooked the fact exercise the sense of touch, 

 that they had previously been discovered in 3. The sudorific apparatus (Vappareil sudo- 

 the Cetacea by Hunter. And it is simply be- rijique) consists of soft, elastic, spiral canals, 

 cause they do not possess any difference of which extend through the entire thickness of 

 note as compared with other Mammalia, (ex- 

 cept in their relative volume to other parts of * S ee Ossem. FOBS. vol. v. pt. i. p. 300, and 

 the labyrinth which Hunter *s careful to point Le9ons d'Auat. Comparee, vol. ii. p. 467. 



