prepared at Berkeley, being completed in May, 1904, after my 

 connection with the University of California was begun. My 

 separation from the collections and the library of the State Labora- 

 tory has rendered impossible some verifications, comparisons of 

 specimens with more recent literature, especially among the algae, 



DISTRIBUTION OP COLLECTIONS BY MONTHS. 



some desirable amplifications from omitted intermediate collec- 

 tions, and the elimination of a few minor errors in the statistics. 



It should be understood that the data of this paper are derived 

 from channel collections, and the conclusions apply only to that 

 region. Conditions of plankton development in the adjacent back- 

 waters, as shown in Part I., differ greatly in volumetric character 

 and seasonal distribution. The composition of the plankton and 

 the seasonal distribution of its constituent organisms also exhibit 

 there many points of difference from those here described for channel 

 waters. 



