88 
PACIFIC SCIENCE, Vol. XVII, January 1963 
Fig. 21. Gians kyushuensis , sp. nov. (holotype), 
16.0 mm X 13.0 mm X 5.5 mm. 
banks-associated molluscan assemblages are 
found from the discontinuous biotopes, i. e., 
southwestern Kyushu (about 129° 30'' E) and 
Izu Islands areas (about 140° E). Latitudinally, 
they are distributed from the southern tip of 
Izu Peninsula (34° 34' N) southward to Tori- 
shima Island (30° 30' N). 
Above all, this study shows how marine mol- 
lusca on the same level under similar ocean 
climate are governed in their distribution by 
the substratum. Moreover, a particular mollus- 
can assemblage (or simply a combination of 
the species) can serve to indicate the sedimen- 
tary characteristics of the banks in the Kuroshio 
area. 
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APPENDIX 
Gians kyushuensis Okutani, sp. nov. (Carditi- 
dae) 
Shell equivalve, dosed, stout, gibbous in 
