the charts of the distribution of the plankton 

 for July and September can give material for 

 judging this question. For example, at the 

 time of the first plankton survey (July 10-15) 

 Labidocera japonica was found at the southern 

 stations on only the westernmost section (in 

 line with Shikotan Island), but on the second 

 survey (September 20) it was discovered also 

 at the southern stations but now on all sections 

 all the way t o the easternmost (in line with 

 Cape Lopatka in Kamchatka). The distance be- 

 tween the southern stations of these sections 

 was about 900 miles. As there were 7 5 days 

 between July 15 and September EG, the mean 

 velocity of transport of the "Japanese" water 

 of the Kuroshio consequently was about 12 

 miles per day. According to hydrological data 

 the velocity of transport of the Kuroshio water 

 (east of Japan) is somewhat less than 12 miles 

 per day, i.e., close to the magnitude which 

 can be defined by the seasonal change in the 

 extension of plankton forms. 



On the basis of this example and also of 

 data on the speed of spread of other neritic 

 species of the zooplankton it is possible to as- 

 sume that the "Japanese" water extended to the 

 east 900 miles in 2-1/2 months with the result 

 that favorable conditions were produced for the 

 survival and development of such species as 

 Labidocera j aponica, Penilia avirostris, 

 Nannocalanus minor, Cop.ilia spp, , anda series 

 of others which were carried away from the 

 coast of Japan and also from the south. 



In the present paper we have attempted to 

 solve to some extent two problems: 1) to sketch 

 the general scheme of regionalization of the 

 planktDn in the waters of the Pacific Ocean off 

 the Kuriles and in the northwestern part of the 

 Kuroshio, and 2) to determine the boundaries 

 of the distribution of some species character- 

 istic of different ecological and zoogeographical 

 groups of the zooplankton, primarily copepods. 



CHIDAMBARAM, K. and D. M. MENON 



1945. The correlation of the west coast 

 (Malabar and South Kanara) fish- 

 eries with Plankton and certain 

 Oceanographical factors. Proc. 

 Ind. Acad. Sci. , v. XXII, sect. B 

 No. 6. 



DAKIN, W. J. and A. COLEFAX 



1933. The marine planktonic forms and 

 their seasonal distribution. Proc. 

 Linn. Soc. NS Wales, v. LVIII, p. 

 3-4. 



FARRAN, G. P. 



1936. Copepoda. Or. Barr. Reef Exped. 

 1928-1929 Sci. Rep. v. Y. /y?_/ 

 No. 3. 



GEORGE, P. C. 



1953. The marine plankton of the coastal 

 waters of Calicut with observations 

 on the hydrological conditions. 

 Jour. Zool. Soc. India, v. 5, No. 1. 



JACOB, P. K. and D. M. MENON 



1947. Copepods of the West Hill. Sea. 

 Proc. Ind. Ac. Sci. v. XXVI, sect. 

 B, No. 5. 



MARINE ATLAS 



1953. Marine Atlas, v. II (Physico- 



geographical). Published by the 

 General Staff of the Sea Forces, 

 1953. 



SEWELL, S. R. 



1932. The Copepoda of Indian Seas. 

 Calanoida. Mrm. Ind. Mus., v. 

 X, 1929a. 



1947. The free-swimming planktonic 

 Copepoda. Systematic account. 

 JohnMurray Exped. 1933-34. Sci. 

 Rep. V. VIII, No. 1. 



LITERATURE CITED 



BRODSKII, K. A. 



1954. Copepod (calanid) fauna and zoogio- 

 graphical regionalization o f thf 

 northern part of the Pacific Ocean. 

 Avtoreferat of doctoral disserta- 

 tion for the Institute of Oceanology. 

 Acad. Sci. USSR, M. 



1948. The free-swimming planktonic 

 Copepoda. Geographical distri- 

 bution. Ibid., V. VIII, No. 3. 



STEUER, 

 1933. 



Zur planmassigen Erforschung der 

 geographischen Verbreilung d e s 

 Haliplanktons besondcr drr Cope- 

 poden. Zoogeographica, 1, Pt. 3, 



CHACKO, P. J. 



1950. Marine plankton from water around 

 the Kriisadai island. Proc. Ind. 

 Acad. Sci., v. XXXI, sect. B No. 3. 



VERVOORT, W. 



1949. Biological results of the SncUius 

 Expedition. XV. Tlie batliypelagic 



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