SUMMARY 503 



that the plankton is imprisoned between the two and prevented from moving ; the two 

 bandings are now wound onto a storage spool in a preservation chamber. The gauze 

 is graduated into numbered divisions and each section may be made to represent one or 

 more miles of sea traversed by adjusting the pitch of the propeller blades. The spools 

 have a capacity for a 250-mile record ; at the end of the run they may be changed like 

 the spools of a roll-film camera and the used ones kept for examination on a special 

 stage beneath a traversing microscope. 



The evolution of the machine is briefly dealt with and the latest machine described 

 in complete detail. 



The method of towing, the process of analysis, the interpretation of results, the 

 catching power of the machine, and the limitations to the method are dealt with (see 

 contents table). 



Possible future developments in machine design are discussed. 



REFERENCES 



Hardy, A. C, 1926. A new method of plankton research. Nature, cxvin, p. 630. 



1935. The Continuous Plankton Recorder: a new method of survey. Rapports et Proces-Verbaux des 



Reunions du Conseil Permanent International pour l'Exploration de la Mer, xcv, pp. 35-47. 



1936. Observations on the uneven distribution of oceanic plankton. Discovery Reports, xi (in the press). 



Hardy, A. C. and Gunther, E. R., 1935. The Plankton of the South Georgia inhaling grounds and adjacent 



zvaters 1926-7. Discovery Reports, XI, pp. 1-456 (p. 255). 



