1921] Schmitt: The Marine Decapod Crustacea of Californa 301 
WV... POSTSCRIEF 
It is of more than passing interest to be able to notice, and compare 
here, the rather close correspondence between the conclusions set forth 
immediately above regarding the local distribution of the decapods 
of the Survey, and those independently arrived at by Packard (1918a, 
1918) as a result of his studies of the ‘‘ Molluscan Fauna from San 
Francisco Bay,’’ and published after the present paper had gone to 
press, viz: 
‘‘The character of the bottom appears to have the greatest sig-. 
nificance in determining the local distribution of the mollusca’”’ 
(1918b, p. 245). ‘‘Depth has little significance in determining the 
distribution of local forms...the significance of the temperature 
factor is obscure’’ (1918a, p. 331). ‘‘The salinity factor is considered 
to be the major one in accounting for the meagerness of the fauna of 
the upper in contrast to that of the other divisions of the bay’’ (1918), 
p. 245). 
Recently in The factors controlling the distribution of the Poly- 
noidae of the Pacific coast of North America, Miss Essenberg (1918) 
has adduced what appears to be further evidence in favor of Point 
Conception as a faunal barrier, marking a dividing line between a 
north temperate zone (extending north to Cape Flattery) and a north 
subtropical zone (extending south to Cape San Lucas). 
But if we treat the species listed by Miss Essenberg in the same 
manner that the California decapods were dealt with under their 
Geographical Distribution above (pp. 281 to 286), we find of the 
twenty-eight species of littoral record (from 100 fathoms or less) 
from off California, that seven (25%), so far as known at present, 
are restricted to the region north of Point Conception, and nine 
(32%) to the region south of it, while twelve (43%) range both north 
and south. 
Of these twenty-eight polynoids of littoral record, the bathymetric 
range of twelve (43%) reaches beyond the 100-fathom line. It does 
not, therefore, seem unreasonable to expect that with more intensive 
collecting and dredging a considerable number of species at present 
only found south, will be found north of Point Conception as well, 
and vice versa, especially in view of Miss Essenberg’s warning that, 
‘‘the distribution of some of the species is as yet inadequately known’’ 
CI918> ps L75)e 
