A table is given of the performance of the current meters at two 

 selected speeds (text table 3 ) • Some of the current meters were quite 

 consistent in their performance over a long period of use. In this 

 category were current meters Nos. 5> 6, and 31» Other meters changed 

 their performance gradually, becoming less free-running with continued 

 use (current meter No. 81). "^he abrupt change in performance of 

 current meter No. 32 on Horizon ' bruise Jlij il^as due to "an accidewtol" ^ 

 change in the pitch of the fclades of the current meter 'a impeller. 



For any given haul, the appropriate calibration graph was used to 

 determine the performance of the current meter (length of the coliann 

 of water strained per revolution) at the speed at which the haul was 

 taken (average rev/sec). The vol^ame of water strained during a haul 

 was determined by multiplying the number of revolutions registered by 

 the cvirrent meter duri.ng a haul by this value, and then teking the 

 cross-sectional area of the mouth of the net (in square meters) into 

 account. 



For the very few hauls lacking reliable current meter readings, an 

 approximate value was obtained which represented the average performance 

 of the current meter at the rate of speed at which the particular hauls 

 were made. Stich values in table I are enclosed by parentheses. 



STANDARDIZATION OF THE HAULS 



For comparability xri.th past data, the same method of standardizing 

 hauls has been employed as that described in a previous report (Ahlstrom 

 19h8). This standard adjusts the number of eggs or larvae in a haul to 

 the nximber in 10 cubic meters of water strained per meter of depth 

 fished by the net. If the vertical distribution of the eggs or larvae 

 has been encompassed, this value is equivalent to the number under 10 

 square meters of sea surface. The reader is referred to the above-cited 

 paper for details. 



SEPARATION OF FESH B3GS AND LARVAE FROM PLANKTON SAMPLES 



Fish eggs and larvae were separated from the other constituents of 

 the plankton hauls by examining the material \inder a low-power microscope. 

 For the majority of hauls (6I47 samples, representing about 70 percent of 

 the hauls) the complete samples wtre examined. Owing to the large 

 voltime of plankton taken in some hauls, it was necessary to fraction 

 these into aliquot portions. A few samples were divided into as many as 

 16 aliquots (6.25 percent each), but most fractioned samples were divided 

 into 2, U, or 8 aliquot portions. For all iiquots smaller than 50 per- 

 cent, two portions of each sample were sorted. A tabulation follows of 

 the number of samples from each cruise that were fractioned and the per- 

 cent of each that was sortedl 



