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change, connecting the most ancient with those of the 

 present day. With the exception of the later Jurassic Crocodilia 

 their bodies are protected with a dermal armour of bony 

 scutes, and in some cases with ventral armour of the same 

 character. The Order Crocodilia is divided into two 

 groups Longirostres and Brevirostres the former are aquatic 

 and good swimmers ; those which lived in the Mesozoic Age were 

 marine or freshwater. The extinct Teleosaur resembled the living 

 Gavial ; their remains are widely distributed from the Lias to the 

 Upper Jurassic. Their latest appearance was in the Upper 

 Chalk of Provence, France ; two Longirostres only survive. 

 Crocodilian remains, Petrosuchus and Pholidosaurus, are found in 

 the Purbeck beds of Langton, near Swanage, associated 

 with terrestrial and freshwater animals. They are inter- 

 mediate between Teleosauridce and the Metriorhynchidce, or the 

 more recent Rhynchosuchidce. The Brevirostres have been found 

 in the Upper Jurassic Beds of Bavaria. The skull is short and 

 broadly triangular, the dorsal -armour is not well developed, and 

 there are no ventral scales ; the limbs are long and slender. 

 Unlike their predecessors they lived in freshwater when the 

 Purbeck and Wealden beds were laid down. Mr. Beccles found 

 some dwarf Crocodiles in the Purbeck beds, near Swanage ; they 

 are exceedingly small, but relative in size to some equally 

 diminutive Mammals with which they were associated and on 

 which they probably preyed. The size of these little Crocodiles 

 does not exceed 18 inches. In all the Crocodilian family the 

 faces of the anterior vertebrae are convex and not concave on 

 both, as is the case with mammals. There is a valvular appliance 

 at the proximal part of the snout by which the water is prevented 

 from entering the glottis, and which acts as a complete partition 

 wall, preventing suffocation when the head is under water, 

 allowing a free passage of air through the outer-nostril when 

 above the surface. This is a necessary provision, as the food 

 of the Crocodile is not restricted to fish only, but consists 

 also of large land-animals which have to be submerged for a 

 considerable time in the process of drowning. The Amphibian 



