CONTENTS OF VOLUME X 

 Plates 1-9 



PAGE 



Title-page i 



Contents Hi 



A Further Study of Variation in the Gopher-Snakes of Western North 



America, by John Van Denburgh 1 



(Published August 6, 1920) 



Description of a New Species of Rattlesnake (Crotalus lucasensis) from 



Lower California, by John Van Denburgh 29 



(Published August 6, 1920) 



Description of a New Subspecies of Boa (Charina bottce utaliensis) from 



Utah, by John Van Denburgh 31 



(Published August 6, 1920) 



Description of a New Lizard (Dipsosaurus dorsalis lucasensis) from 



Lower California, by John Van Denburgh : 33 



(Published August 6, 1920) 



Undescribed Tipulidae (Diptera) from Western North America, by 



Charles P. Alexander 35 



(Published August 6, 1920) 



Three New Species of Dolichopodidae (Diptera) from California and 



Nevada, by M. C. Van Duzee _ 47 



(Published August 6, 1920) 



Two New Species of Syrphidse (Diptera), by A. L. Lovett 51 



(Published August 6, 19^) 



Notes on Some Undescribed Calif ornian Helices, by S. Stillman Berry.... 53 



(Published August 11, 1920) 



A New Genus and Species of Grasshopper from California, by Morgan 



Hebard _ 71 



(Published December 29, 1920) 



Color Changes and Structure of the Skin of Anolis carolinensis, by 



Charles E. von Geldern 77 



(Published February 12, 1921) 



Report of the President of the Academy for the Year 1920, by C. E. 



Grunsky 119 



(Published July 2, 1921) 



Report of the Director of the Museum for the Year 1920, by Barton 



Warren Evermann 128 



(Published July 2, 1921) 



Index 165 



JUNE 11, 1923 



