6 
Crocodiles — Geosaurus. 
Crocodilia. 
Wall-case, 
No. 2. 
Table-case, 
No. 3. 
Belodon. 
Wall -case, 
No. 2 
diles. Professor Owen lias constituted two groups, based on 
these modifications of the vertebrae. The Crocodiles belong to 
the procoelian section (vertebrae concave in front), and are 
divided into a brevirostrine , or short-snouted section, containing 
the Alligator, the Crocodile, and the Tertiary genus D iplocynodon ; 
and a longirostrine , or long-snouted section, embracing the 
Garials, Tomistoma, Thoracosaurus, and Rhamphosuchus. 
The Amphicadiaii section (vertebrae concave at both ends), 
embraces Hylceochampsa , also a second brevirostrine section 
including Theriosuchus , Goniopholis , Nannosuchus , and Owenia- 
suchus, and a second longirostrine section for Pholidosaurus and 
Petrosuchus , all from the Wealden and Purbeck beds. 
The older secondary forms belong to the Teleosaurid^e as 
Pacosaurus , Metriorhynchus, TeleidosauriLS, Machimosaurus , Pelago- 
saurus , Steneosaurus, and Teleosaurus. The earliest of these 
Crocodilian reptiles is named, Belodon (Fig. 8), having long 
and pointed slightly- curved teeth, longitudinally grooved, and 
Fig. 7.— Crocodilus Spmccri (Buckland). Upper view of skull restored, from the 
London Clay of Sheppey (about £ nat. size). 
Wall-case, 
No. 2. 
Geosaurus. 
with elongated jaws like the modern Garials ; the other, named 
Stagonolepis, resembled the existing Caimans, but with an elon- 
gated skull like the Garials ; the body was covered by bony 
scutes. Both these reptiles are from the Trias, the former from 
Stuttgart, Germany; the latter from Elgin, Scotland. In the 
Oolitic and Liassic series the old type of long and slender- 
jawed Teleosaurs and Steneosaurs (Figs. 9 and 11), with 
strong bony scutes, was abundantly represented. 
Here are exhibited the type specimens of Geosaurus , 
from the lithographic stone (Upper Oolite) of Solenliofen, 
Bavaria. Baron Cuvier inferred, from the form and structure 
of its skull, that Geosaurus held an intermediate place between 
the crocodiles and the monitors, but was more nearly related 
to the latter. The orbits are large and the eyes w'ere protected 
by bony sclerotic plates, like those of Ichthyosaurus . It had 
