452 PKOCEEDIKGS OF THE GEOLOGICAL SOCIETY. [DoC. 15, 



straight, and apparently fitted for sutiural union -with the corre- 

 sponding margin of another scute, while the other margin, is rounded 

 off, and is either thin, or, if thick, shelves off rapidly to a thin edge. 

 Hence I conclude that these dorsal scutes formed, as in the Teleo- 

 sauria, only a double series, and that their external edges were not, 

 except perhaps in the caudal region, connected with other scutes. 



The irregular angulated scutes only remain to he accounted for. 

 They have much resemblance to the small scutes which are scattered 

 along the margins of the great dorsal shield of existing Crocodiles ; 

 but it is possible they may have belonged to the narrower part of 

 the tail. 



To sum up in a few words the results of this long inquiry, it is 

 evident that, in its dermal armour, Stagonolepis is altogether a Cro- 

 codilian EeptUe. 



Bones of the Stagonolejois. — I will abstain, at present, from par- 

 ticularly describing the impressions of ribs, of two scapulae, and of 

 the posterior face of the second sacral vertebra of Stagonolepis, 

 because all these parts nearly resemble the corresponding bones of 

 ordinary Crocodilia. Had my acquaintance with the organization of 

 the Elgin reptile been confined to the remains already mentioned, in 

 fact, I should have been fully justified, according to the ordinarily 

 accepted canons of paleontological interpretation, in prophesying that 

 any other parts which should be brought to light would conform very 

 closely to the Crocodilian, and especially the Teleosaurian, type. It 

 was a useful warning, however, to find that I should have been 

 unsupported by the event, had I done so; for all the other re- 

 mains depart, more or less widely, from the ordinary Crocodilian 

 type of organization. The smallest amount of difference is percep- 

 tible in the femur, an incomplete cast of part of the shaft and distal 

 end of which bone (of the left side) shows that it was thicker and 

 stouter in proportion than that of the Crocodile. The impressions 

 of the articular surfaces of the condyles, again, are so rough and 

 irregular as to lead to the suspicion that they were covered by 

 imperfectly anchylosed epiphyses — which is the reverse of a Croco- 

 dilian character. 



The cast of the only example of a metacarpal or metatarsal bone 

 which has come to light also exhibits proportions which indicate a 

 much shorter and thicker foot than the corresponding bone in the 

 modern Crocodiles, o^ndi, a fortiori, than in the Teleosauria. The pro- 

 portions of these bones, then, lead us to look for a stouter thigh and 

 a shorter and broader foot than exist in the Crocodilia. On the other 

 hand, the single natural cast of a long and nearly straight bone, 

 which I can only regard as an ungual phalanx, indicates a length of 

 claw wholly foreign to the Crocodilian foot. 



The vertebrae, whose more or less perfect natural casts have 

 passed through my hands, all belong either to the dorsal, the sacral, 

 or the caudal series. The impression of part of a sacral vertebra, to 

 which I have akeady alluded, shows that in this region the structure 

 of Stagonolepis was very similar to that of known Crocodilia', 

 but the dorsal and caudal vertebrae are remarkable, partly for the 



