ics . cada ascent SB ot feves nee CMM Toth approximately 2 cm were removed from the samples before processThe plankton was filtered through No. 1 Whatman paper and ing. about two grams were transferred to a 1.5-inch stainless steel planchet, dried with an infrared lamp, and then counted aboard ship. The remainder of the plankton sample was preserved for future use. Amounts of plankton were determined volumetrically. A 50 ml portion of sea water and plankton was poured into a Buchner funnel with No. 1 Whatman filter paper. The amount of Plankton remaining on the filter paper was determined by subtracting the amount of filtrate from the original amount of sea <2 -ROPENMRES Be water and plankton (50 ml). After returning to Eniwetok Marine Biological Laboratory the shipboard estimates of the volumes of the plankton samples were revised. The corrected volumes were calculated by multiplying the dried sample weight of the individual samples by the ratio of the average estimated volume to - the average dry weight. Finally, volumes in ml were converted directly to wet weights in grams. Bathythermograph casts were made by the ship's crew at each Station during the cruise for the purpose of defining temperature change with depth. Water Samples: Samples were collected at the surface by bucket and at 25, 50, 75 and 100 meters by means of a Nansen water bottle (Fig. 4). The surface water samples were processed aboard ship and the other samples at the EMBL. One liter of surface water was passed through a Millipore filter using Millipore AA paper. counted. The filter paper was saved and Prom the filtrate two 100 ml samples were processed