Thomas Bell

A History of British Reptiles Thomas Bell

HISTORY BRITISH REPTILES, By THOMAS BELL. INTRODUCTION. THE Reptilia corstitute a cIass of vertetrated animals of which the structural characters are as follow -They have cold blood, - that is to say, their power of producing animal heat is so limited as scarcely to be appreciable, and not sufficient, therefore, to keep up all standard temperature of the body, nor to prevent it from following all the thermal voriatios of the atmosphere or water by which they are surrounded. The integument is covered with hard and dry cuticle in various modifications of form, in same constituting broad plates, in other imbricated scales. The heart is in all cases trilocular,-that is to say, it is composed of two nuricles and a single ventricle the respiration is exclusiveIy pulmonary throughout life, and their reproduction is oviparous...