732 SIMI DIRS IRON SLGUDIGINIES, 
large Python-like forms. The Eocene of New Jersey has yielded 
one form, Zztanophis, and the Puerco of New Mexico Flelegras. 
The Eocene of Wyoming has yielded Boavus, Lithophis, and Lim- 
nophis. 
The Miocene layers of both this country and Europe have 
afforded many scattered fragments that belong mostly to living 
families. The Pliocene and the Pleistocene contain only genera 
and species of living forms. 
CROCODILIA. 
The Crocodilia are lizard-like forms of generally, large size 
possessing many characters that indicate their origin from the 
Dinosaurs and the Rhynchocephalia. The tail is long and powerful, 
the jaws armed with strong, simple teeth, the skull flattened, 
and the anterior end produced into a rostrum of varying length; 
there is generally developed in the skin a series of bony plates 
that in some forms is confined to the back, and in others extends 
to the skin of the abdomen as well; there are generally devel- 
oped abdominal ribs in the body wall. 
The order is divided by Zittel into three suborders : 
Parasuchia. 
Pseudosuchia. 
Eusuchia. 
The Parasuchia are the nearest of all the order to the ances- 
tral stem of the Crocodilia. The possession of paired anterior 
nares, located far back on the upper surface of the skull, of 
large preorbital openings in the skull; the structure of the 
base of the skull and the palatal region, and’ the structure of the 
shoulder girdle are all characters that unite the suborder with 
Dinosaurs and the Rhynchocephalia. 
Lelodon, the most common form, was about nine feet long; 
the skull extended forward ina long, high, and laterally com- 
pressed rostrum; the jaws were filled with strong, simple teeth ; 
there were two rows of plates extending down the middle of the 
back, and others less regularly developed in the skin of the 
sides; the limbs were weak and probably had about the same 
