PROCEEDINGS 



OF THE 



CALIFORNIA ACADEMY OF SCIENCES 



Fourth Series 



Vol. I, pp. 323-374 January 17, 1912 



EXPEDITION OF THE CALIFORNIA ACADEMY 



OF SCIENCES TO THE GALAPAGOS 



ISLANDS, 1905-1906 



IV 

 THE SNAKES OF THE GALAPAGOS ISLANDS 



BY JOHN VAN DENBURGH 

 Curator of the Department of Herpetology 



CONTENTS 



Plates XXII-XXX 



Page 



Introduction 324 



Previous Collections and Studies 324 



The Genus Dromicus Bibron 327 



Key to the Galapagos SPEaES 329 



The Material for this Study 329 



Origin of the Galapagos Snakes 331 



Suggestions to Future Students 336 



Discussion of the Species 336 



Dromicus hiserialis (Gunther) 336 



Dromicus hoodensis, new species 338 



Dromicus dorsalis (Steindachner) 341 



Dromicus occidentalis, new species 347 



Dromicus occidentalis helleri, new subspecies .... 349 



Dromicus slevini, new species 351 



Dromicus steindachneri, new species 353 



Hydrus platurus (Linnaeus) 355 



Explanation of Plates • 356 



January 15. 1912 



