In addition to 14 species described or simply mentioned by TOKUNAGA and NISHIAMA, 29 species and subspecies were described (including spines of two genera just mentioned) by HAYASAKA and MORISHITA, and HAYASAKA in 1947-1948, in the 4 papers referred to above. Of the 29 forms 13 belong to SPATANGIDAE. The fossil echinoids range from Eocene to Pleistocene in Taiwan.
The new subgenus
Peronellites of the genus
Peronella, proposed by HAYASAKA and MORISHITA, is diagnosed : “Test elliptical in outline ; genital pores four, wanting in interambulacrum, V : apical system and proximal ends of petals markedly vaulted up”.
The new genus
Sinaechinus with its type species,
kawaguchii, proposed by HAYASAKA should be cancelled. Considering the tube-like peristome with an anteriorly projecting labrum, and the duplication in front of the peripetalous fasciole unique features, owing to the shortness, of reference works in Taiwan, the Recent specimen from Tonkin Bay and an incomplete fossil specimen from the Pliocene sandstone in Tainan Prefecture, Taiwan, were named Sinaechinus kawaguchii gen. et sp. n.
On rehabilitating from Taiwan in 1949, NISHIYAMA of the 'Tohoku University kindly informed me of the fact that the, double-fascioled echinoid had been known since 1851 when J. E. Gray described
Faorina chinensis from the Chinese waters. NISHIYAMA moreover favored me with copying the descriptions and pictures of the species by GRAY, KOEHLER, and CLARK. By parusing these descriptions, and comparing the descriptive features of the Tonkin Bay specimen with them, it has become evident that the specimen is nothing but
Faorina chinensis GRAY, although no pictures copied from GRAY and KOEHLER show the.duplication of the peripetalous fasciole. The fossil specimen from Taiwan, though incomplete and deformed, also may be identified. with
Faorina chinensis, or, possibly it may be a subspecies if the relative lowness of the test is its original, natural shape.
Three species from, the Pleistocene Riukiu Limeston of Tokuno-shima are described in the Notes side by side with allied or comparable Formosan forms, simply because of convenience.
On comparing this fossil fauna and the Recent one as has been known up to present, there is only one species common to both, i. e.,
Echinoneus cyclostomus : and only 4 genera are represented in both faunas. The cause of this divergence might be that : while the fossils were buried where they had been, the Recent.material was mostly found stranded, although some of them belonged to the systematic collection carried out by KAWAGUCHI.
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