Fossils from the Upper Mnsashino of Kazusa and Shimosa. QJ 



As a fossil, a single nmtilated example was found with the 

 greater part of the spire lacking. It is about 25 millim. in dia- 

 meter. 



Fossil occurrence. — Shi to. 



Living. — Central Japan. 



Family Tritonidae. 



Genus TRIÏOX, Moiitfort. 



SI, Trifott fenuilivatus, Lischke. 



PI. III. Fig. 8. 



Triton temiiliratus. Lischke, Jap. Meerescouch., Ill, p. 30, pi. II, figs. 18, 19. Tryon, 



Mau. Conch., Ill, p. 22, pi. XII, fig. 105. 

 Tritonium teniiiliratinn. Pilsbry, Cat., p. 47. 



An adult and a young specimen. 



The shell is fusiform with large body-whorl. The whorls are 

 generally more or less angulate a little above the middle. The 

 surface above the angle is flat and gently sloping, while below it is 

 more or less vertical and somewhat contracted toward the lower 

 suture. The ^'arices number three on the last two whorls with the 

 fourth one at the boundary between the penultimate whorl and the 

 one preceding it. Between the varices there are many close longi- 

 tudinal threads, some of which are coarser than others and often 

 assume the appearance of small ribs. Spiral threads about eight 

 on the penultimate whorl three above the angle, one upon it and 

 usually double (divided into two by an impressed line), and the 

 rest on the vertical wall and unequal in size. The body-whorl 

 possesses many spiral threads, of which the three above the angle 

 are equal-sized, while those below the same are alternately large 

 and small although sometimes there are two smaller ones be- 

 tween the larger. Periphery rounded, Aperture obovate. Outer 

 lip with a varix without and sulcate within. The canal in our 

 specimens is broken, but it is evidently long, narrow, and some- 

 what bent. Height about 36 miUim. Diameter 13.5 miUim. 



Fossil occurrence. — Shito. 



Living. — Central and Western Japan. 



