UNIVERSITY OF CALIFORNIA PUBLICATIONS 
IN 
ZOOLOGY 
Vol. 18, No. 13, pp. 299-336, plates 12-13, 6 figures in text April 20, 1918 
A QUANTITATIVE ANALYSIS OF THE 
MOLLUSCAN FAUNA OF SAN 
FRANCISCO BAY 
BY 
E. L. PACKARD 
re 
CONTENTS 
PAGE 
UB AVS NCO) AON ap ee Se SPO ree Ree en Os 9 Pee rer ERP OCT Eeever ret, Me -Le 
General distribution of the Mollusca ...................... Pisa oes bee AB aces Kash raes onda sae es 301 
Physical characters of San Francisco Bay .......-.2..--.-.-:-0s---:.css+sseesestensenenneeneae 301 
The molluscan fauna of San Francisco Bay ................-..-.--.-. 
WIGONOWIC CONSIMETATONS <..5- 2222-2 enccaroneneedorasscaveseceecsantccsascectavecsoncnane 
Factors governing the distribution of the Mollusca 2 
PEG EVO GON OCP GU eesesec ae cacresenann st cstacecenes ac entansenspossnectsncessunnaceutescescenasds-udceUscorade never 318 
PROM TNOMEGONE YE, OLN DOLGOUL co sectce cece ce ccer tances nencn cee cee wance ceaceaee Aron otveentesacsseaeesecvica= 318 
PEGS NEMO Fina Om SEL UNI TA ye rere wae sexe c a atc eae ees hon asc cune cba cease sono tan tae ene uae eeencothanesoraucons) OME 
IRIS HUEIOTUBUOUGONE DORAN ULE, <c.ccsccaret- feck nen oie nnve pees aeceeeacte mateo ee cies otaaeenea tne atasneteoes OOH 
Relation to the available food supply 
Relation to the biotic enviroMMent <u... cites ss eeececscdeeecsseseceeeeeeeneeenees OOO 
ESSER TYR ir pare ea sca sacean Kn Sean pend orata nse Se eee Ease decan aac eeacccaccatstezee) OO 
EUV ETOCS, cage ec So i RE an RM SEB ee 302 Ee 332 
TL AAS HREM ATS COREG | Ak Fs SRS eee erect Peer ae hc oe a ee eee Dh) 
BBB [OAR rh OTN OOTP LOS Ue cree acct acc some ca nel onc pape caer g tae ne SE ancy no naprartasadtent OOS 
INTRODUCTION 
Improved methods of procedure already applied in several different 
regions of the world have revealed many of the actual conditions under 
which the marine animal lives. Increased knowledge of such matters 
has been made possible, locally, through the Biological Survey of San 
Francisco Bay made by the United States Bureau of Fisheries. 
The survey was made by the U. 8. S. ‘‘Albatross’’ under the 
direction of a board consisting of Dr. F. B. Sumner, naturalist, Pro- 
fessor Charles A. Kofoid, and Commander G. H. Burrage, U. 8. N., 
