Xantus' Snake (Hypsiglena ochrorhyncha: Yarrow, Henry C. 1882. Check list of North American Reptilia and Batrachia with catalogue of specimens in U. S. National Museum. Bulletin of the United States National Museum (24):1-249); Spotted Night Snake (Hypsiglena ochrorhynchus: Van Denburgh, John. 1897. The reptiles of the Pacific Coast and Great Basin: An account of the species known to inhabit California, and Oregon, Washington, Idaho, and Nevada. Occasional Papers of the California Academy of Sciences 5():9-236); Spotted Night Snake (Hypsiglena ochrorhynchus ochrorhynchus: Van Denburgh, John. 1922. The Reptiles of Western North America: An Account of the Species Known to Inhabit California and Oregon, Washinton, Idaho, Utah, Nevada, Arizona, British Columbia, Sonora, and Lower California. Volume I. Lizards. California Academy of Sciences, San Francisco. 556pp.); Spotted Night Snake (Hypsiglena ochrorhyncha: Schmidt, Karl Peterson and D. D. Davis. 1941. Field Book of Snakes of the United States and Canada. C.P. Putnam and Sons, New York. 365pp.); Night Snake (Hypsiglena torquata: Schmidt, Karl P. 1953. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.); San Diego Night Snake (Hypsiglena torquata klauberi: Schmidt, Karl P. 1953. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.); Sierra Nevada Night Snake (Hypsiglena torquata nuchalata: Schmidt, Karl P. 1953. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.); Spotted Night Snake (Hypsiglena torquata ochrorhyncha: Schmidt, Karl P. 1953. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.);