10 University of California Publications in Zoology [Vol. 23 



Spirontocaris franciscana, Crago lonvae, Pachycheles holosericus, Pet- 

 rolisthes rathbunae, Paguristes ulreyi, Dardanus jordani, Pylopagurus 

 holmesi, and Homola fax<oni. 



The forty -seven species taken in the course of the biological survey 

 of San Francisco Bay are, following the systematic treatment of each, 

 more or less fully discussed from the point of view of their distribution 

 and habitat within the region covered by the survey. With the 

 exception of five obtained only at shore stations, Upogebia pugettensis, 

 Emerita analoga, Oedignathus inermis, Petrolisthes cinctipes, and 

 Pachygrapsus crassipes, and three from miscellaneous collections, 

 Acantholithodes hispidus, BandalUa ornata, and Oregonia gracilis, 

 these forty-seven species were taken at 133 (89%) of the 150 dredging 

 stations, and 152 (50%) of the 305 hydrographic stations at which 

 collecting apparatus was employed. These stations are distributed 

 as follows : 



Regions of Number of stations at which Number of stations at which 

 the bay collecting apparatus decapods were 



(for limitations was employed taken 



see p. 323) 



Dredging Hydrographic Dredging Hydrographic 



Upper 22 80 - 22 37 



Middle 73 109 66 43 



Lower 38 107 28 72 



Outside 17 9 17 



Total 150 305 133 152 



A summarized discussion of the distribution of the bay fauna 

 together with a few remarks on the geographical distribution of the 

 California decapods in general concludes this paper. These remarks 

 are confined to littoral records only, for aside from the fact that the 

 deep sea fauna, as a rule, is more or less cosmopolitan in its distri- 

 bution our knowledge of that occurring off California is too incom- 

 plete at the present time to permit of more than a mere listing, which 

 is included in appendix I. Beside this distributional list of all the 

 California decapods, found in appendix I, there are two other appen- 

 dices, which, however, deal only with the survey data. All extensions 

 of range recorded are based on material contained in the collections 

 of the U. S. National Museum. After figures indicative of salinity the 

 expression per mille (°/oo) is to be understood. 



With the exception of those designated U.S.N.M., obtained through 

 the courtesy of the U. S. National Museum, the line drawings, both 

 copies of figures already published as well as the several original 



