UOLL CALL ijj 



Class II — Reptilia — Turtles, snakes, alligators, and lizards. 



Characteristics: Cold-blooded; usually covered with scales and fre- 

 quently bony plates ; air breathers. 



Order 1 — Rhynchocephalia — "The old-timers," Sphenodon. 



Characteristics : Biconcave vertebrae often containing remnants of noto- 

 chord; quadrate bone immovable; parietal eye present. This group i.« 

 represented by one genus of lizards, Sphenodon, found only in New Zea- 

 land. 



Order 2 — Crocodilia — Crocodiles and alligators {Crocodiliis, Alligator). 



Characteristics : Anterior appendages bearing five digits, jiosterior four 

 with trace of fifth ; longitudinal slit constitutes cloacal opening; vertebrae 

 procoelous. 



Order 3 — Chelonia — Turtles and tortoises (Amyda, Eretmochelye, Terrapene, 

 Testudo, Chelonia). 

 Characteristics : Body surrounded by bony case forming a carapace and 

 plastron; toothless jaws ; immovable quadrate bone; appendages typi- 

 cally with five digits. 



Order 4 — Squamata — Snakes and lizards (Phrynosoma, Heloderma, Tham- 

 nophis). 

 Characteristics: Usually with horny epidermal scales or plates; movable 

 quadrate bone; vertebrae usually procoelous; ril)s with single heads. 

 This order is usually subdivided into two sub-orders: lizards (Sauria) ; 

 and snakes (Serpentes). 



Orders 5-8 — /)z/;o.s<7;/m — Fossil reptiles (Ichthyosaurs, Plesiosaurs, Pterodac- 

 tyls, Dinosaurs). 



In these groups belong such forms as the fishlike reptiles (Ichthyosaurs) ; 

 the long-necked reptiles (Plesiosaurs) ; the flying reptiles (Pterodactyls) ; 

 and the giant reptiles (Dinosaurs). 



