10 GUIDE TO THE FOSSIL REPTILES, AMPHIBIANS, FISHES. 
Wall-case plaster cast of the best of these fossils, now in the Yale 
Tabl^cases University Museum, is exhibited, and justifies the late 
l_ 4 . Professor Marsh’s restoration of the animal reproduced in 
D. Fig. 5. It will be noted that there is a rudder-like expansion 
of the skin at the end of the long tail. Another long-tailed 
Pterodactyl ( Dimorphodon ) is also represented by some well- 
preserved portions of skeletons in slabs of Lias from Lyme 
Regis, Dorsetshire. Its head is disproportionately large and 
of remarkably light structure, with large teeth in sockets in 
front, small teeth behind. Its hind limbs are also relatively 
large and stout; and its long tail is strengthened by bony 
tendons. A plaster cast of the skull of another Pterodactyl 
(Scaphognathus purdoni) , from the Upper Lias of Whitby, is 
noteworthy as displaying the shape and proportions of the 
brain (Table-case 1). 
Order IIL— CROCODILIA. 
Wall-eases At the present day crocodiles live only in tropical and 
Table-Leases su k-t r °pi ca l regions; but in the early part of the Tertiary 
5-12. period they had a much wider distribution, perhaps in 
consequence of the greater extent of genial conditions at 
that time. There cannot be much doubt, for example, that 
during the Eocene period the climate in the latitude of 
southern England was sub-tropical. True crocodiles lived in 
the rivers at the mouth of which the London Clay was de¬ 
posited ; and skulls of Crocodilus spenceri are exhibited from 
this formation near Sheerness in the Isle of Sheppey (Table- 
case 6, Wall-case 2a). Alligators (Liplocynodon), closely 
related to those now existing in tropical America, are also 
represented by fine skulls and numerous other remains from 
the Upper Eocene sands of Hordwell Cliff, Hampshire; 
while the same animals are proved by numerous fragmentary 
specimens to have survived in France and southern Germany 
until the beginning of the Miocene period. Even the long¬ 
snouted gavial ( Gavialis ), at present confined to the Indian 
region, seems to be represented by a portion of a jaw from the 
Middle Eocene of Bracklesham Bay, Sussex (Table-case 5); 
and one large skull from the Miucene of Austria, of which a 
plaster cast is exhibited in Wall-case 3, is essentially iden¬ 
tical with the skull of Tomistoma, which now survives only 
in the Malay Peninsula and Archipelago. In warm countries 
where crocodiles still live, they were much moie numerous 
and varied in former times than at the present day. There 
