species had been described in the restricted area under discussion. Dr. 

 Hubbs looked forward to the studying of vertebral variation in correla- 

 tion with the special temperature and pressure combination of the deep 

 sea. 



Referring to Dr. Graham's difiiculties in making complete hydrody- 

 namic calculations for shallow water areas, Dr. TuUy explained a method 

 by which this could be achieved with good approximation to accuracy. 



Dr. Hubbs wished to have suggestions as to how any of this data 

 could be used to contribute to increased fisheries catches. Dr. Graham 

 was not prepared to speak to the point, emphasizing only that the work 

 being carried out was basic to all biology to be done in the area. 

 Biologists should be able to make the relevant correlations with the data 

 as it is presented to them. 



Dr. Johnson asked whether plankton samples were being secured, 

 what were the main types of fish encountered, and what was known as 

 to their life-histories. The fish concerned mainly were tuna and mackerel, 

 and, regarding plankton, surface hauls only were being made, not below 

 4-5 ft. from the surface, with half-hour tows. The large zooplankton 

 were principally concerned here. Dr. Johnson concluded by suggesting 

 that attempt be made to get the nets down much deeper. Dr. Graham, 

 in agreeing, briefly pointed out the heavy pressure of work on research 

 trips, and the hmited amount that could be undertaken in the short 

 time available to the personnel on board. Dr. Deacon briefly supported 

 Dr. Graham's contention that these physical oceanographical results 

 were basic to fisheries and biology in the area. The data being 

 accumulated was a very necessary foundation. 



Some discussion took place on the irregularities in temperature data 

 encountered at a depth of 100 metres. The transition surface was by 

 no means a level one, and no doubt the Spilhaus technique would have 

 revealed more irregularities. A problem for study was the inflow from 

 the China Sea. 



Dr. Hiatt further supported Dr. Deacon's remarks on the fisheries 

 aspect. It was desired in the Hawaian tuna work to have an oceano- 

 graphic vessel accompany the fisheries vessels to get correlatable physical 

 data. This bulked very important in the ecology of pelagic fishes. 

 Dr. Tully recalled three-year investigation in which more than fifteen 

 fishermen had been equipped with sample bottles and reversing ther- 

 mometers, the titrating being, of course, done ashore. The results 

 were examined, and there was no correlation of the catch with the moon 

 phase, the temperature, or the salinity. Only the "hours fished" 

 showed correlation with catches — i.e., " the man who had his line in the 

 water caught the fish." It was not yet justifiable to assume that 

 hydrographic data will ultimately give a reliable indication of where 

 fish are likely, to be. Dr. Graham believed that we would ultimately 

 find correlation between oceanographical data and the movements and 

 presence of tuna. Temperature stratification influenced the phyto- 

 plankton, which in turn influenced the food-cycle of the plankton leading 

 upward to the food of the tuna. In short phytoplankton is the link 

 between physical oceanography and fisheries predictions. 



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