FISHERY INDUSTRIES OF THE UNITED STATES, 1934 321 



office. Statistics of production of wholesale and manufacturing firms 

 are published only for commodities or geographical areas where the 

 production of three or more concerns may be grouped. Every effort 

 IS made to publish only those figures which will not reveal individual 

 enterprise. 



CONVERSION FACTORS 



It is the policy of the Bureau to show the detailed catch figures of 

 all products in poimds for the sake of uniformity and for purposes of 

 comparison. Follo^^^ng such a policy presents certain problems. In 

 the case of fish there is little difficulty since in very rare instances are 

 such products reported in units of measure other than pounds. For 

 shellfish, however, the units of measure may be bushels, sacks, barrels, 

 or thousands of shellfish, gallons of meats, etc. These many units 

 make standardization difficult, but when coupled with the wide varia- 

 tion in the requirements or definition of some of these units in the 

 various States the problem becomes even more complex. 



All bivalve mollusks are reported in pounds of meats in the detailed 

 catch tables presented in this report. In addition, there are included 

 supplementary" tables for most of the sections, which give data on the 

 production in bushels. These supplementary tables also give the 

 production of certain other shellfisli, such as crabs, in number. 



Oysters. — Probably the greatest problem in presentation of fishery 

 statistics in uniform units of measure is in the case of oysters. Usually 

 the production of oysters on the Atlantic and Gulf coasts is reported to 

 Bureau agents in bushels ; and prior to the data obtained for the year 

 1930 conversion from bushels to pounds of meats was effected on the 

 basis of a uniform yield of 7 pounds of meats to the bushel. However, 

 recent investigations have shown considerable variation from this 

 figure. There follows a table which gives the results of these studies 

 of the measures used for oysters in the various States and of the 

 average yields per bushel. This table presents the factors that have 

 been used in the oyster statistics given in this report. 



Measures and yields of oysters ' 



• Data for the New England, Middle Atlantic, and Chesapeake States are for 1933. 



Other data are for 



