TEETIAEY LIMESTONE NEAR SAG AR A, TÖTÖMI. 94 1 



nearly smooth, lower tliree spirnlly sciili)tnro(l with h'ra-, wliicli 

 number 5 on the pennltiin;ite and ll^ on tlie last wliorl, and are 

 generally wider than their interstitial furrows: anions- the Tirai on 

 the l)ody whorl the siiUstitnral is tlie Jar^-est. Apertun; indistinct, 

 but nearly ovate (?) 



Height of tlie shell -I.Smni. 



Width 4:^mm. 



Spiral angle 8G° 



Approximate ratio of body whorl to entire shell 70 : 100. 



T. melrimii'iisis is allied to some of the living species. In the 

 form of the shell, the nund)er of whorls, and the liras <^n the body 

 vrhorl, it resembles T. arh'Nsis Montronzier LSHO (Tryon, Mtouial of 

 Concholofiti^ vol. X, p. lOlî IM. 45, Figs. 9(), 1)7), from which, however, 

 it is distinguished in its sculpture, the living one having spiral ribs 

 Avhich are narrower than the interstices. In the last point it coincides 

 with T. ayijijro^toniiis Linn, 1758 (The same bo(jk, ]>, lî)7, PI. 40, 

 Fig. 18 ; ri. 46, Fig, 8) ; but not in the other characters of the shell 

 of this species. 



It is mostly found as casts, of which parts of the limestone bed, 

 common on the eastern flank of the Mekamiyama, are full. The 

 specimen figured was kindly given me by Mr. Sadahe Yagi, of Mekami« 



The Tertiary f<3rmati(jn, within which the limestone makes its 

 appearance in a local manner, subdivides into an Upper and Lower 

 series.^ 



1. Mr. Xakashium has given these divisions the names of Upper Gigawa Tertiary and Lower 

 Oigawa Tertiary, and considers the former to be probably Pliocene and the latter Miocene. 



