The Importance of the Facial Pit of the Northern Pacific Rattlesnake

The Importance of the Facial Pit of the Northern Pacific Rattlesnake(Crotalus viridis oreganus) Under Natural Conditions in Southern British Columbia.

An MSc  thesis submitted by William Barton Preston UBC, 1964.

See full PDF : preston_1964_importance_of_facial_pit_of_north_pac_rattlesnake_southern_bc_thesis

 

reference: The Western ratttlesnake:

http://www.env.gov.bc.ca/wld/documents/rattlesnake.pdf

photos from the bc govt. publication above