346 CALIFORNIA ACADEMY OF SCIENCES. 



that these beds antedate the close of the ice age and may 

 have been deposited early in the Pleistocene, or in the 

 Pliocene. 



It is a matter of judgment and precedent as to which 

 of those two periods we shall assign these beds. On ac- 

 count of the distinct character of the fauna, we cannot 

 compare it with known Pliocene areas, and therefore our 

 only resource is to fall back on the old method of per- 

 centages and say that as all the beds of known Quater 

 nary age have a higher percentage of forms living in the 

 present fauna, we may conditionally assign these beds to 

 the Pliocene. On the other hand the arctic character of 

 the fauna would suggest that these deposits were laid 

 down during the early part of the Pleistocene in what is 

 known as the Ice age. 



It may be of interest to note that the above list as com- 

 pared with the latest published list of California fossils 

 (1888)* shows thirty-three species not noticed before as 

 fossils at San Pedro, eleven species not previously noticed 

 as fossil and fifty-four not before known as Pliocene, 

 while one species has only been known as Miocene. 



Sauta Barbara and San Diego. — A study of the species 

 recorded as Quaternary from Santa Barbara and San 

 Diego in Dr. Cooper's " List of California Fossils " re- 

 veals the fact that at those places even a larger percent- 

 age of the Quaternary fauna is not found in the present 

 fauna, and suggests that there exist at those places similar 

 conditions as to those found at San Pedro, that is, two 

 distinct horizons that have not been differentiated, the 

 lower of which may be correlated homotaxially with the 

 Pliocene. 



yapan. — Dr. David Braunst in his study of the geology 



* 7th Ann. Eep. State Mineralogist, pp. 223 et seq. 



t Memoirs of Sci. Dep., Univ. of Tokio. No. 4, 1881, p. 77. 



