XVIII . Vision 22 



XIX. Vocalization 23 



Sound Recordings , 23 



XX. Physiology and Biochemistry 24 



a . Blood 24 



b. Body Weight 24 



c. Digestive System 24 



d. Endocrine System 25 



e. Integument 26 



f . Lipid Metabolism 27 



g . Locomotion 27 



h. Nervous System/Neuromuscular System 27 



i . Regeneration 29 



j . Reproductive System 30 



k. Respiration 31 



1 . Temperature 31 



m. Water Metabolism 31 



XXI . Venoms/Toxins 32 



XXII . Parasites and Disease , 32 



XXIII. Miscellaneous , 34 



XXIV. Distribution 35 



A. General 35 



B. United States 35 



General 35 



States (listed alphabetically) 36 



C . Canada 50 



General 51 



Provinces (listed alphabetically) 51 



XXV. Fossil Record 53 



IV 



