138" Anatomical Observations on 



The question here is not merely to rectify an accredited 

 error, and to defend the antients from the injustice done 

 them by some of the moderns. I must also call the atten- 

 tion of naturalists to a singular fact in regard to organiza- 

 tion. Nothing, indeed, can be more paradoxical than tlie 

 head of the crocodile; all those parts which in other ani- 

 mals a'le on the sides, are in the crocodile thrown backwards. 

 The temporal bone itself projects backwards a good deal be- 

 yond the cranium : it is elongated, and transformed into 2 

 double condyle, the functions of which it performs. Every 

 thing has in some measure been said of the head of the cro- 

 codile, by consul; ring it as composed merely of two jaws, 

 for the cranium is so small and so displaced that it escapes 

 the first exainiuat'on. It is found below and a little before 

 the occipital plate; the brain, or rather the ganglion, con- 

 tained in its cavity, which is exceedingly narrow, is conti- 

 nued pretty far forwards, so that the organs of sight and 

 of hearing are situated below and a little behind it. 



Another anomaly equally wortliy of remark is, 1st, That 

 the lower jaw is a sixth longer than the upper and the cra- 

 nium. i?d, That the lower jaw exhibits a cavity with two 

 facets, where the horns of the temporal bone are articulated 

 by a ginglynnis. 3d, That the occipital condyle is on the 

 same line as the four condyles of the temporal bones, so 

 that the head is really retained towards its points of articu- 

 lation as the lid of a box is by its hinge. 4th, That as the 

 two jaws have only a simple motion from the top down- 

 wards, they cannot be moved separately to the right or to 

 the left, to subject the aliments to a sort of trituration. 



On examining a living crocodile, or one prepared, as is 

 customary in collections, it is hardly possible to believe that 

 the head terminates at the extremity of the jaws; one looks 

 for the osseous box which contains the brain, and which 

 in all other animals manifests itself externally under the 

 form of a frontal protuberance. The observer thinks he 

 gees it towards the anterior part of the neck, which is sym- 

 metrically swelled up, and which is generally taken for the 

 complement of the head : but this swelling arises from the 

 presence of thf crotaphite muscles, which are pretty volu- 

 minous, and which in a great measure are lodged between 

 the straight and oblique muscles. 



Difil-renccs so great in the form of the head necessarily 

 occasion others in the organs which correspond directly 

 with it ; and it is indeed found that the cervical column is 

 composed of seven vertebrae, which are distinct, but com- 

 bined ill their articulation in such a manner that they are 



not 



