PROTEO-SAURUS.
This animal has been found at different times in several parts of England, in the lias, near Bath, and elsewhere, having been mistaken for a crocodile at different times, while some had imagined that its bones belonged to a bird, and others to a fish. It is still, however, so far imperfect, that the bones of the pelvis are yet unknown. The finest specimen yet found is at the College of Surgeons, in Lon don, and has been described by Sir Everard Home, in the Philosopical Transactions.
The length of the skeleton, from the end of the nose to that of the tail, is about thirty-nine inches. It resembles those of the Proteus tribe in having four feet, together with cupped vertehrze ; a structure that does not belong to the lizards, in which there are ball and socket joints; but appearing intermediate between the fishes and the lacerta, it was first called Ichthyosaurus. Sir Everard Home, how ever, finding that this form of the vertebra was the only resemblance which the specimens which he had first examined bore to the fishes, and also finding a similar structure in the vertebra of the proteus from Germany, of the syren of Carolina, and of the Mexican axolotl, was induced to change the name to that which it bears at present.
This animal differs now from the Proteus tribe, includ ing the three just named, in having long ribs, which are attached to a sternum regularly formed, and which meet it as in the chameleon; differing, however, in having no joints; and likewise in having no arches for the reception of gills. Thus the chest must have been capacious, and
it must have resembled the lacerta in its manner of breathing, while it agreed with the Proteus in having two modes of progressive motion. Still it differs from the former in the mode in which the ribs are fixed on the spine, in the bony plates of the eye balls, and in the shape of the legs and feet. It is therefore not a lizard, and must consequently form that intermediate genus which is ex pressed by the name that has here been adopted.
On Fossil Mainnliferous .dninzals, or Quadrupeds..
For the arrangement and description of these we are indebted to Cuvier, who has bestowed an attention on this subject which, united to his accurate knowledge of com parative anatomy, has rescued from confusion a very large department, formerly little understood. For an ex tended description of that of which we can only give a very slender sketch, we must refer our readers to his very splen did and voluminous work on this subject. \Ve shall select and dwell on the most interesting objects, without any regard to their order in the zoological system.