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sent distribution of pelagic fisheries of the world. The to have led to the relative neglect of coastal waters severity of northern climates, which does not help pro- as sources of food. Almost the entire east coast of duction of adequate agricultural crops, must have also S. America (Brazil, Argentina, etc.), many parts of contributed to the greater concentration on the part Africa, Asia and Australia provide examples of un- of the peoples of these climates on fisheries as in in- exploited or inadequately exploited waters for fisheries dustry, and traditions of feeding and clothing changed where food from agricultural and other sources has only very slowly under compelling circumstances. been available for a great majority of the popula- The abundance of food in regions with highly deve- tions, In these areas fisheries provide accessory food, laped agricultural, horticultural and livestock indus- not'an important item of food as in the countries of tries in certain tropical and sub-tropical regions seems the temperate and boreal regions. BIOLIOGRAPHY. 10. Lohmann, H., (1908) .-Wissensch. Meeresunter N. F. Abth. Kiel, 10: 131-370. 1. Allen. E. J., (1927).-Food from the Sea. Journ. Mar. 11. Norman. J. R., (1936).-A History of Fishes, 463 pp., Biol. Assn., 11: 380-390. London, 2nd Edn. 2. (1923).-Progression of life in the Sea. 12. Paton, J., (1936).John. Murray Expedition, Sci. Rep., Rep. ~dtbh'Assn. Hull, 15 pp. 2(1). 3. Anon, Encyclopaedia Brdtannica (14th edition) 13. Russell, F. S., (1935) .-On the value of certaln plank- ton animals as indicators of water movements in the English channel and North Sea. Journ. Mar. Biol. 4. Hardenberg J. D. F., (1938).-Marine Biological Fishery Assn., 20: 209-232. problems 'in the troaics. Arch. Neerland. Zool. 3 Suppl. (Nierstrasz vol:) pp. 65-73. 14. , (1933) .--Study of copepods as a factor in oceanic economy. Proc. 5th Pacific Congress, pp. 5. Hardy, A. C., G.T.D. Henderson & C. E. Lucas, (1938-37). 2023-2024. -The Ecological relations between the herring and the plankton investigated with the plankton indi- 15. Schott, G., (1935).--6eographie des Indischen und cator. Journ. Mar. Bid. Assn., 21: 147-281. Stillen Oz?ans. Hamburg, pp. 1-413 & charts. 6. Harvey. H. W. (1942).-Production of life in the Sea. 16. Sverdrup, H. U., M. W. Johnson, & R. 13. Fleming, Cambridge Phil. Soc., Biol. Rev., 17: 221-246. (1942 j .-The Oceans, thelr Physics, Chemistry and General Biology. 1060 pp. New York. 7' EcologbalR" W'Animal Geography,& K' 597 Schmidt'pp. New York. '- 17. Tressler, D. I(., (1923) .-Marine Products of Commerce, 762- pp. New York. 8. Howat, G. R., (1945).-~ariations in the Camwaltlon 18. Thompson. E. P. L H. C. Qilson, (1937).John hlurray of the sea in Weat Africa waters. Nature. 155: 415-417. Expedition. Sci. Rep., 2(2). 9. Herdman, W. A., (1923) .-The Founders Of OCeanO- 19. Wimpenney, R. S., (1936-37) .--S?e of Diatoms, Journ. graphy, 340 pp. London. Mar. Biol. Assn., 21: 29-60. Part 11: THE BIOLOGY OF PELAGIC FISHES N. Kesava Panikkar. THE HERRINGS AND ANCHOVIES. would have been negligible but for the enormous numbers in which they appear, providing a source Both in numbers and in economic value the not only of edible fish,,but also of fish oil, fish meal fishes be!onging to the family Clupeidae rank first and fish manure. This group comprising about sixty among the food fishes of the world. They are repre- species includes the herrings of the North Atlantic, sented in all temperate and tropical seas and often the true sardines of S. Europe, S. America, the form large shoals swimming on the surface and Pacific and S. Africa, the menhaden of Atlantic performing long migratory journeys. Although coasts of America, the sprat, the pilchard and the most of them are marine, there are a few species closely related forms shoaling along the coasts of which occur in freshwater and, a still larger number S. Europe, West Africa, India, the Far East, Australia that ascend rivers at some phase of their life history. and New Zealand. The pelagic species, which are more in the habit of forming shoals than the coastal and estuarine species, Taxonomic Dificulties. The taxonomy of clu- are mostly of a small size and, at any rate, never peids presents considerable divergence of views. The exceed a foot in length. In fact, most species are earlier workers distinguished ,only one genus CEupea much smaller and, especially so are the tropical forms for the herring, the sprat, the pilchard, the shad and averaging from 4 to 8 inches; their economic value the many other sardines but in recent years this has been subdivided into numerous genera. The (193 1) has described the phenomenon of "swim" herring of the Atlantic, Clupea harengus, is the best in herrings-his explanation being that "herring in known of all clupeids; in fact, many of the recent a normal state can see the nets and avoid them, so ideas relating to fishery science has grown around this that the sea may be full of herring, yet none caught. species. It is common to both sides of the North When however, they are under the influence of Atlantic in the cooler latitudes and extends even to crowd excitement (due to panic, sexual excitement .the seas north of Asia. In the North Atlantic. the or migratory impulse) herrings are more or less un- species has given rise to many types of fisheries in. able to see the net, and are caught". different parts of the year. Thatlks to the studies of Hjort, Heincke, Lea, Schnalcenbeck, Fulton, Ford Herrings that are landed can usually be classified and many other fishery naturalists, we have a fair into three categories:-(I) Full fish in which the amount of all round information on its habits and roes and milt are fully developed, (2) spawners in movements. Herring is the only known instance which the gonads are actually in the running condi- of a clupeid whose eggs are demersal and not tion and (3) spent fish. pelagic; the spawning grounds in the North Atlantic are now well known. The fish spawns both in spring C. harengus extends to Arctic waters both on and the autumn. the Atlantic and Pacific sides, but the main species of Pacific herring is C. pallasii which is also interest- The growth is slow; the spring herring at the ing in the fact that it is discontinuously distributed, end of the year is hardly 2 inches long while the being found in the White Sea north of Europe and autumn herring for the same period would show only in the sea east of Kamchatka. a much less growth and is rarely over 1%". These differences in growth and the habits attendant have The Closely related to the herring given rise to herrings being recognised broadly as Sprat. is the sprat (Clupea sprattus) spring spawners and autumn spawners; some authors found all round the British Isles, consider that these are different races. Both males extending in the North Sea as far north as Norway and females attain sexual maturity in about 4-5 where the fish are extensively canned as "sardine". years. It is in connection with the herring that the It is much smaller than the herring and were for- question of races in commercial fishes assumlld im- merly considered as their young ones. The spawn- portance. The pioneer work of Heincke on different ing begins in January and lasts till June or July. samples of herring distributed all over rhe Atlantic The egg is pelagic. led him to state that he was able to distinguish two main groups of herring, viz., Spring or coastal herring The The South European Pilchard and Autumn or sea herring. He was further able Pilchard. (Sardina pilchard~~s)on the other to distinguish many local groups hand is a warm water species and Race and varieties, whose validity, how- is rarely found in Northern waters. It is also a Studies. ever, is disputed by other workers, small species, occurring in large numbers along the but each particular fishery is coasts of Southern parts of Ireland and England, often associated with a definite "race" of France, Spain and Italy, and the coasts of North herring. The great Scottish Fishery is concerned West Africa. This is the well known European with the sea or Autumn herring as also the great sardine which has heen highly developed as an English drift net fishery on the East coast. The industry in the countries of S. West Europe. The Norwegian and Baltic herrings which contribute to spawning ground is 20-40 miles out at sea but the great fisheries in Scandinavian countries comprise fishery is concerned not with mature spawning indi- viduals but with juvenile stages. The species is Spring or coastal herrings. Both drift net and found in the warmer Southern waters of Europe trawl fisheries in a particular area may be based on during winter. the same race and stock. According to Ford ( 1933 ) the Plvmouth winter drift net fisherv for herrine" is The Menhaden On the American side of the subject to seasonal as well as daily fluctuation; this & Shad. Atlantic to the south of Cape has been indicated as beinn" caused by the variations Hatteras, .the clupeids are repre- in the number and character of the boats engaged in sented by the Menhaden (Brezloortia tyrannus) and the fishery and to the intensity of fishing. These, the American shad (Alosa sapidissima) both of however, do not fully account for the fluctuations which contribute fisheries of great magnitude.