376 University of California Publications in Zoology [Vol. 2-2 



more sensitive to environmental changes or less able to make their 

 own way. If this be true, at both La Jolla and Pt. Hueneme Pro- 

 rocentrum micans Ehr. is evidently the typically stable species and 

 Ceratium furca (Ehr.) Clap. u. Lach. shows similar tendencies. For 

 this particular year it is clear that dinoflagellates present even less 

 evidence than diatoms that there is a regular seasonal sequence in 

 species. 



Species and Genera 



Since I have already in former papers (Allen, 1921, 1922) desig- 

 nated the more common forms and discussed certain characteristics 

 exhibited by them in this region it is scarcely necessary to include 

 such details in this paper or any other until our observations have 

 been carried over enough years and localities to make such discussion 

 more nearly accurate instead of merely suggestive. We have in 

 expectation a period of at least five years of pier collections in this 

 series which we hope may give ground sufficient for a revised state- 

 ment of details. 



Note. — In accordance with the recent movement toward condensa- 

 tion of scientific matter detailed discussion has been almost entirely 

 omitted from this paper and (still more important) 228 pages of 

 tables have been omitted. No place of deposit of such tables has yet 

 been designated so that it will be necessary for those desiring further 

 information to write to the Director of the Scripps Institution at 

 La Jolla, California. 



