2 ART. 1?. — S. TOKUNAGA : ON TF1E 



The genera found in the Cainozoic formation are the following: 

 Salenia, Coptosoma, Temnopleurus, Strongylocentrolus, Fibularia, 

 Clypeaster, Laganum, Fch'marachnius, Echinodiscus, Aslri- 

 dypeus, IZarionia, Echinolampas, IAnthia, Schizasier, Frenasler, 

 Hypsospatangus and Brissopsis. 



Among these, Frenasler, Harionia and Hypsospatangus are 

 forms not living in the recent seas ; and all except the last, which 

 was collected from the Neogene Tertiary of Hokkaido, were found 

 in the Eocene of the Bonin Islands. 



Astriclypens is a genus restricted to Japan and China, being 

 represented by a single living species A. manni Verill. This 

 genus differs from all others in possessing five large lunules. The 

 fossil is a new species, and was found in the Miocene of Kai, 

 Formosa and Riukiu (Loochoo Is.) 



Coptosoma has only one living species, C erenulare A. Ac, 

 also found fossil in the Pliocene of the Province of Sagami. 



Fchinodiscus is represented in Japan by one living (F. lœvis 

 Klein) and one fossil form (F. formosus Yosh.), the latter having 

 been collected by myself from the Miocene of Formosa and 

 Riükiu. 



IÂnthia, which is no longer living in Japan, shows in the 

 fossil form a wide distribution, being known from Kanazawa in 

 Kaga ; Sakae, Hidaka and Ikari in Shinano ; Tsurushi and 

 Hazzaki in Hitachi ; Anrakujö in Uzen ; and Asahigawa in 

 Ugo. The formation in which it is found is probably Pliocene. 



Schizaster has two or perhaps more species. One is S. 

 nummuliticus Tok. found associated with Nummulites in the 

 Eocene of the Bonin Islands ; another is S. recticanalis Yosh. 

 found together with Linthia nipponica Yosh. in Sakae. Besides 

 the above two, I have found two indeterminable species of the 



