768 BIOLOGY OF THE SEAS OF THE U.S.S.R. 



the flora may be considered a consequence of severe winter conditions and a 

 southern geographical situation. 



The central and southern Primor'e are characterized by a predominance of 

 annual and seasonal species, by their patchy mosaic-like distribution, by 

 the reduction of the Fucii and Pelvetiae to secondary species, and by the 

 formation of a red sea-weed border of Iridophycus, Coralina pihdlifera sp. 

 Rhodomela larix, and Laurensia sp. in the lower littoral. 'Whereas 85 species 

 of sea-weeds have been recorded for the littoral of the northern Primor'e, in 

 the southern 108 species were found ; moreover, the number of red algae is one 

 and a half times greater. In the northern Primor'e the number of brown algae 

 species exceeds that of the red, while in the southern Primor'e there are twice 

 as many red algae as brown' (T. Shchapova, 1956). 



In the very south of the Primor'e, Fucii disappear altogether, Pelvetiae 

 become scarce and Gloiopeltis is poorly developed, while the blue-green sea- 

 weeds become abundant. Similarity with the tropical littoral exists in the 

 general thinning of the algae cover, in the development of seasonal and 

 ephemeral forms and in an increase in specific variety. Secular macrophytes 

 migrate into the sublittoral. Changes in the vegetation of the coastal strip of 

 the Primor'e are accompanied by alterations in the animal population, the 

 latter acquiring a north-boreal character in the northern part of Tartary 

 Bay, and a warm-water, south-boreal aspect in the central and southern 

 Primor'e. 



The first published results of the quantitative investigations of the bottom- 

 living fauna of the Far Eastern Seas are those of I. Zachs (1927), K. Derjugin 

 (1939) and K. Derjugin and N. Somova (1941), who studied the bottom- 

 living fauna in Peter the Great Bay in 1925 and 1931-33. Zachs was the first 

 to investigate the littoral fauna of the Far Eastern Seas. 



Peter the Great Bay is a vast shallow which falls away steeply to the great 

 depths of the Sea of Japan. The bottom-living fauna of the Bay (Fig. 381) 

 is distributed according to definite zones. Derjugin distinguishes 41 biocoe- 

 noses from the supralittoral down to the greatest depths (Figs. 382 and 383). 



The quantitative and qualitative development of the supralittoral and lit- 

 toral flora and fauna is limited by the small tidal range. The supralittoral 

 zone is characterized by the development of the sea-weeds Rivularia atra 

 and at times of Rhizoclonium riparium, and among the animals by Ligia 

 cinerascens and the small crabs Brachinotus sanguineus and Doclea bidentata. 



In the upper horizon of the littoral zone the rock sea-floor is characterized 

 by growths of Gloiopeltis capillaris (funori algae), occasionally by Ulva and 

 Sargassum and frequently by Littorinae (L. sitchana and L. aqualida), 

 Patella sp. and Turbo sangarensis; by Chthamalus challenged of the genus 

 Ligia cinerascens and the crabs Brachinotus sanguineus and Doclea bidentata. 



The lower horizon of rocky littoral is encircled by a fringe of Corallina 

 pellulifera and characterized by a much greater variety of both sea-weeds 

 {Leathesia difformis, Ralfsia, Chordaria) and animals (Hydroida, Actinia, 

 young Ostrea; the Amphipoda Allorchestres zivellinus and Orchestia ocho- 

 tensis ; the Gastropoda Thais limoi ; the starfish Patiria pectinifera and Aphe- 

 lasterias japonica and others). 



