every 4 hours along the llO'W. meridian. On 

 the remainder of the cruise, one lowering was 

 made between stations 90 miles apart, and two 

 between stations 120 miles apart. During the 

 drifting period, in addition to station casts, 16 

 BT observations were taken at various times. 

 BT casts were made just before and after each 

 oceanographic station. 



BT observations from the Gilbert 

 numbered 240 (table 3). They were made every 

 6 hours while running between Honolulu and 

 11°N., and between the Marquesas ajid Tahiti, 

 and every 3 hours on runs between 11°N. ajid 

 the Marquesas. A single lowering was nnade at 

 each surface fishing station in the Marquesas 

 and Tuamotus. 



~ Water transparency and color observa- 



tions were made from both the Smith and the 

 Gilbert. The transparency measurements were 

 made with a standard 30 -cm. Secchi disc; water 

 color was designated by connparison with the 

 Forel standards. These data are presented in 

 tables 9 and 10. 



Productivity observations 



The rate of carbon fixation by photosyn- 

 thesis was determined with the radioactive car- 

 bon (C'*) method, as developed by Steemann 

 Nielsen (1952) and modified by Doty (King et al. 

 1957), employing water samples taken from the 

 Smith . Surface inorganic phosphate analyses 

 were obtained simultaneously with the C de- 

 terminations. These data are presented in table 

 11. 



The Manning cruise data included 240 

 BT records (table 4). The lowerings were 

 made every 6 hours traveling to, from, eind 

 between the lines of longline fishing stations. 

 A lowering was made just after setting the 

 longline gear, just before and after retrieving 

 it, and midway between fishing stations. 



Surface water samples for salinity 

 ajialysis were taken by the Smith at each BT 

 lowering between Honolulu and the Equator, 

 also at each BT lowering between oceanographic 

 stations north of 2°N., and occasionally at BT 

 lowerings during the rest of the cruise. These 

 data are included in table 2. 



Surface water samples for the determi- 

 nation of salinity cind inorganic phosphate were 

 teiken from the Gilbert once a day between Ho- 

 nolulu and 5°N., and at alternate BT lowerings 

 between 5°N. and the Marquesas. Salinity 

 samples were taken at each live -bait fishing 

 station. All samples were analyzed ashore 

 (table 5). 



From the Manning , surface salinity 

 samples (table 4) were taken at every other BT 

 cast on runs to, from, etnd between lines of 

 fishing stations, ajid at each fishing station. 



On all vessels, standard weather 

 observations were made 4 times daily, except 

 they were omitted when the vessels were in 

 bays or harbors. They were made only twice 

 daily during the breaJcdown period of the Smith , 

 and the 1200 (GMT) observation was not taken 

 on the Gilbert and Manning during fishing peri- 

 ods. The observations, as encoded and record- 

 ed on USWB Form 1210-F, are presented in 

 tables 6, 7, and 8. 



Three types of plankton hauls were nnade 

 from the Smith, all with a 1 -meter net of 656 

 Nitex (aperture width 0.66 mm.). Except dur- 

 ing the runs between Honolulu and the Equator, 

 an oblique 0-60 meter, 30-minute haul was 

 made each day at about 1130 local time, at the 

 same time as the C^^ sampling. Each night be- 

 tween 2000 and 2200 local time, an oblique two- 

 net tandenn haul was conducted, saimpling at 0-60 

 meters and 0-200 meters. Innmediately follow- 

 ing this, paired 30 -minute surface tows were 

 made. The station data and plankton volumes 

 are presented in table 12. 



Eight 30-minute surface tows, employing 

 a similar 1 -meter net, were made froin the 

 Gilbert in the vicinity of the Marquesas and 

 Tuamotus. The station data and plankton 

 volumes are presented in table 13. 



Surface trolling 



Except when otherwise engaged, all the 

 vessels did surface trolling during daylight 

 hours with varying numbers of lines. The 

 catches and related data for each of the three 

 vessels are listed in tables 15, 16, and 17. The 

 common and scientific names of fish caught are 

 listed in table 14. 



Longline fishing 



Routinely, 60 baskets of 1 1 -hook longline 

 fishing gear were set from the Manning at each 

 fishing station; 38 stations were fished success- 

 fully. The gear used was of POFI design, as 

 described by Mann (1955). Pacific herring 

 ( Clupea pallasi) was used for bait. The station 

 data and catch per 100 hooks fished are pre- 

 sented in table 18; the catch record in numbers 

 of fish is presented in table 19. 



