L@2 ON THE STAGONOLEPIS ROBERTSONI AND THE 
surface at some distance from the anterior margin. The highest 
point of the ridge is far nearer the posterior than the anterior 
margin, 
The inner faces of the scutes are smooth, concave from side to 
side, and slightly convex from before backwards. 
Scattered about between the ventral and cervical, and the cervical 
and dorsal shields, there are many small and irregular detached 
scutes, of all sizes down to 3ths of an inch in length. The smallest 
of them are simply incipient ossifications in the dermis which under- 
lies the ridges of the epidermic scales, and they present no sculpture. 
In fact they correspond with the apices of the ridges of the larger 
scutes. In some of larger size, which present a certain amount of 
sculpture, the apex of the ridge is altogether posterior, and the scutes 
very closely resemble the smaller ¢rregular angulated scutes of 
Stagonolepts. 
Other existing proccelian Crocodilia present a far more complete 
dermal armour; and certain Alligators, of the genus or subgenus 
Jacare} are not surpassed, so far as I am aware, by any recent 
Crocodilia, and certainly not by any of the fossil members of the 
group; though Cuvier calls 7Zeleosaurus Cadomensis “le mieux 
cuirassé” of the group to which it belongs. I shall describe the 
dermal skeleton of the /acare at length in another place ; but I may 
remark here, that the broadest part of the dorsal shield exhibits. 
eight or ten scutes in each transverse row, and that all the dorsal 
scutes overlap their successors by their posterior edges, and are 
united to one another by strong serrated sutures. The ventral 
shield consists, in its broadest part, of 12-14 scutes in a transverse 
row. Each scute, except the two outermost of the series, has four 
straight sides, the anterior of which presents a large, smooth, articular 
facet, while the posterior overlaps the facet in its successor. The 
lateral edges unite in firm serrated sutures. The outer faces of these 
scutes are quite flat, and their ornamentation is so very similar to 
that of the Szagonolepis, that it would require very close attention to 
distinguish a cast of the one from a cast of the other. Multitudes of 
small, irregular, posteriorly pointed, osseous scutes cover the skin of 
the sides of the body, and extend on to the limbs. 
Dermal Scutes of Fossil Crocodilia and Teleosauria—Among the 
1 Alligator luctus, like Crocodtlus vulgaris, has no ossified ventral scutes. Cazman 
palpebrosus has ventral scutes like those of /aca/e, of which I have examined two species, 
J. fisstpes and J. sclerops. YT have nowhere been able to find the slightest allusion to the 
existence of this singularly developed ventral armour in modern Crocodzlia, (See concluding 
Note, p. 117.) 
