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 include 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 



Production of Three Species of Mollusks for the Year 1916 



My a arenaria 



San Francisc-o Bay 161,891 lbs. $8,094.55 



Tomales and San Francisco Bay 366,939 18,346.95 



Bodega Bay 19,702 985.10 



Total 548,532 $27,426.60 



Paphia staminea 



Bodega Bay 1,034 lbs. $103.40 



Saxidomus nuttalli 



Humboldt Bay 43,488 lbs. $2,609.28 



San Francisco Bay yields more than 161,000 pounds of Mya 

 arenaria, 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 occasionally 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 frequenth^ 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. 



