Class Reptilia (Latin, reptare = to crawl).  Reptiles, such as snakes, lizards, turtles, alligators, and crocodiles are adapted to land and must breathe with their lungs.  Unlike amphibians, reptiles have dry, scaly skin that protects them against dehydration. 

One of the most adaptive features that allowed reptiles to be successful species on land was ability to lay eggs (amniotic egg with protective shell) on land.  Few reptiles give birth to live young.

The common term cold blooded (ectotherm) refers to organisms including reptiles that regulate their body temperature by moving in and out of the sun.  Majority of reptiles are carnivorous, and all are bilaterally symmetrical.