5. The winch is a steel drum 4 feet long and 

 3 feet in diameter with a 1,5- inch pipe axle. 

 The water stream is dissociated from the 

 support cable and the powerline at a terminal 

 assembly mounted on one edge of the drum. 

 Rotation is controlled by a reversible 3/4-hp. 

 A.C. gear motor with an automatic brake. 



6. A 1.5-inch I.D. polyethylene hose ex- 

 tends from the winch to the filtering unit, 

 which consists of a wobble plate type water- 

 meter, a quick acting double-throw valve and 

 two filtering funnels set in trash cans. Fil- 

 tered water flows from the cans through 

 outlet hoses to the scuppers of the vessel. 



7. Each filtering funnel has windows 

 screened with 105 //-mesh stainless steel 

 filtering cloth. A collecting bucket bayonet 

 mounted on the neck of the funnel has a bottom 

 screen of the same cloth which is covered 

 by a friction-fitted cap while the funnel is 

 filtering. 



8. Removing and preserving a sample takes 

 2 or 3 minutes, so the filtering unit is easily 

 operated by one man. 



9. With 100 feet of hose out, the collector 

 tows at a depth of 5 or 6 meters at a vessel 

 speed of 9 knots. It has been operated con- 

 tinuously for periods of about 72 hours. 



10. E scapement through the screen of the col- 

 lecting bucket and the size of mutilated zoo- 

 plankters indicate the lower and upper size 

 limits of quantitative collection to be 0.2 mm. 

 and 12.0 mm. respectively. 



11. The error due to escapement through 

 the filtering surfaces appears to be negligible 

 between the above sizes. 



12. Better sensing and recording apparatus 

 is needed for depth-of-tow and temperature 

 information and considerable improvement is 

 needed in the winch if the system is to be 

 used for towing at various depths. 



ARON, WILLIAM. 



1958. The use of a large capacity portable 

 pump for plankton sampling, with notes 

 on plankton patchiness. Journal of 

 Marine Research, vol. 16, no. 2, p. 158- 

 173. 



CALIFORNIA, STATE OF, MARINE RE- 

 SEARCH COMMITTEE, 

 1950. California Cooperative Sardine Re- 

 search Program, Progress Report, 

 1950. Sacramento, State Printer, 54 p. 



CASSIE, R.M. 



1959. An experimental study of factors 

 inducing aggregation in marine plankton. 

 New Zealand Journal of Science, vol. 2, 

 no. 3, p. 339-365. 



COLLIER, ALBERT. 



1957, Gulf-II semiautomatic plankton sam- 

 pler for inboard use. U.S. Fish and 

 Wildlife Service, Special Scientific 

 Report — Fisheries No. 199, lip. 



GEHRINGER, JACK W. 



1952, An all-metal plankton sampler (model 

 Gulf III). In High speed plankton sam- 

 plers, U.S. Fish and Wildlife Service, 

 Special Scientific Report — Fisheries 

 No. 88, p, 7-12. 



HAND, CADET H., and LEO BERNER, JR. 

 1959. Food of the Pacific sardine (Sardinops 

 caerulea). U.S. Fish and Wildlife Serv- 

 ice, Fishery Bulletin No. 164, vol. 60, 

 p. 175-184. 



HARDY, A. C. 



1939. Ecological investigations with the 

 continuous plankton recorder: object, 

 plan and methods. Hull Bulletins of 

 Marine Ecology, vol. 1, no. 1, p. 1-57. 



LITERATURE CITED 



AHLSTROM, ELBERT H., JOHN D. ISAACS, 

 JAMES R. THRAILKILL, and LEWIS W. 

 KIDD. 

 1958. High-speed plankton sampler. U.S. 

 Fish and Wildlife Service Fishery Bulle- 

 tin No. 132, Vol. 58, p. 187-214. 



19 



WIBORG, K. F. 



1948. Experiments with the Clarke- Bumpus 

 plankton sampler and with a plankton 

 pump in the Lofoten area in northern 

 Norway. Fiskeridirektoratets Skrifter, 

 Serie Havunders0kelser (Reports on 

 Norwegian fishery and marine investi- 

 gations), vol. 9, no. 2, 32 p. 



MS #1269 



GPO 939988 



