CROCIDOLITE-BEARING ROCKS OF CALIFORNIA 659 



A report on the subject is in preparation and will be published by the U. S. 

 Geological Survej'. 



CROCWOLITE-DBARING ROCKS OF THE CALIFORNIA COAST RANGES 

 BV GEORGE D. LOXJDEKBACK AND \VM. J. SHARWOOD 



[Abstract] 



Although in no great quantity in any one place, crocidolite-bearing rocks 

 have been found to be rather widely distributed in the Coast ranges of Cali- 

 fornia. They may be classed as crocidolite-bearing cherts or quartzites and 

 crocidolitic schists. A petrographical description was given, analysis pre- 

 sented, and mode of occurrence described. Evidence was offered that many 

 if not all of the rocks are derived from radiolarian cherts, and that they are 

 formed by the introduction of soda into the rock by solution. 



PRnilTIVE CHARACTERS OF AMERICAN TRIASSIC ICHTHYOSAURS 



BY JOHN C. MERRIAM 



[Adstracf] 



The following characters generally appearing in the Triassic Ichthyosauria 

 may be considered as survivals of characteristics of ancestral shore forms. 

 Where the term "relatively" has been used the unexpressed comparison is with 

 the Jurassic ichthyosaurs. 



1. Limbs relatively large and first two segments relatively long. 



2. Hind limbs relatively large. 



3. Epipodial, metapodial, and phalangeal elements often elongated and with 

 shafted median region. 



4. Number of phalanges in each digit relatively small. 



5. Number of digits not increased beyond five. 



6. Pelvic elements relatively heavy ; inferior elements much expanded ; 

 ischium and pubis not fused. 



7. Skull generally relatively short compared with the length of the trunk 

 region. 



8. Jaws relatively short. 



9. Maxillaries relatively long and premaxillaries relatively short. 



10. Orbits relatively small in the earliest forms. 



11. Vertebral centra averaging relatively long. 



12. Anterior cervical vertebrae not fused. 



13. Neural spines of vertebrae relatively thick. 



14. Zygapophysial facets of upper arches in the anterior portion of the 

 vertebral colunui not united or brought into the same plane. 



15. Caudal intercentra large and united ventrally to form large Y-shaped 

 chevrons. 



FAUNA OF THE ASPHALT BEDS EXPOSED NEAR LOS ANGELES, CALIFORNIA ' 



BY JOHN C. MERRIAM 



This paper was published in Science, new series, volume xxiv, 1906, 

 pp. 248-250. 



