UNIVERSITY OF CALIFORNIA PUBLICATIONS 

 Bulletin of the Department of Geology 



Vol. 3, No. 12, pp. 249=263, PI. 21=24. ANDREW C. LAWSON, Editor 



NEW ICHTHYOSAURIA 



FROM THE 



UPPER TRIASSIC OF CALIFORNIA. 



BY 



John C. Merriam. 



CONTENTS. 



Introduction 249 



Relationships and systematic position 250 



Detailed description of new genera and species 253 



Leptoeheirus, new genus 253 



Leptocheirus zitteli 253 



Vertebra and ribs 253 



Anterior arch 254 



Anterior limbs , 255 



Posterior limbs 257 



Skull : 258 



Dentition 259 



Toretocnemus, new genus 259 



Toretocnemus californicus 260 



Vertebrae and ribs .• 260 



Posterior arch 261 



Posterior limbs 261 



Anterior limbs 263 



INTRODUCTION. 



In a large collection of Upper Triassic saurian material which 

 has recently been presented to the University of California by 

 Miss A. M. Alexander there are two Ichthyosaurian species 

 differing considerably from any that have been described. 

 Though we are as yet only partially acquainted with their 

 structure, they seem to be generically distinct from all of the 

 known forms. Both specimens were obtained from exposures of 

 the Trachyceras horizon of the Hosselkus limestone occurring a 

 few miles northeast of Winthrop, Shasta County, California. 



