1918] Packard: Quantitative Analysis of Molluscan Fauna 313 
number of edible clams. Only a few of these, however, are extensively 
used for food. Unfortunately data for the production of mollusks 
within California are available only for the year 1916. Even these 
data are incomplete, since they inelude only the figures for those clams 
handled by the wholesale dealers. The following figures have been 
kindly furnished by the Fish and Game Commission of California. 
TABLE 4 
Propuction or THREE Species or MOLLUSKS FoR THE YEAR 1916 
Mya arenaria 
op drblibhginWort(cte ile | hye aeerert te eestrerer eres 161,891 lbs. $8,094.55 
Tomales and San Francisco Bay ...... 366,939 18,346.95 
SOC GEES BLY.) oaccncesasecioencuccsenevsnnsenicyraveesse 19,702 985.10 
RG UEUD scx sxeemanee Peas salsa ee tees L ARES ELSsoMaE EE 548,532 $27,426.60 
Paphia staminea 
PERO LOO NEN Lie acca tanccexncescmaxmasency-sardeecst= cs 1,034 lbs. $103.40 
Saxidomus nuttalli 
PRSLTaNAN TOOL) ES UOT gece crcucs  tearonsesoxsoyareoxnens 43,488 lbs. $2,609.28 
San Francisco Bay yields more than 161,000 pounds of Mya 
arcnaria, having a value of over $8000. These figures represent 
only a small part of the actual yield, as may be seen by referring to 
table 4. The present yield of the bay is thought by many local clam 
dealers to be much less than it was ten or more years ago. There 
are, however, no figures available upon which to base an estimate of 
a former yield. The wholesale price of this clam ranges from 5 to 
8 cents per pound, the average being about 6 cents. Figures are 
not available for the 1916 yield of Paphia staminea nor Mytilus edulis, 
which are oceasionally harvested within San Francisco Bay. The 
hard shell clam brought in from Bodega Bay and elsewhere sells 
for 9 or 10 cents wholesale. The mussels frequently sell for as 
much as 121% cents retail, under normal conditions of the market. 
The other clams mentioned above are rarely on the local market, and 
therefore the prices are variable, depending upon the sporadic supply. 
The market conditions even for the mud clams are rather unstable, 
due in part to the uncertainties of harvesting, which under present 
methods depend upon a favorable tide, since dredging methods are 
not yet employed. 
The dredging operations of the ‘‘ Albatross’? within San Francisco 
Bay have yielded data from which rough estimates of the average 
numbers per acre of the different clams can be calculated. 
