54 -^ r t. 6.— M. Yokoyama: 



4-2. Siphonalia trochulus, (Reeve). 

 Pl. II. Fig. 14. 



Siphonalia trochulus. Dunker, Index Moll. Mar. Jap., p. 16. Tryon, Man. Conch., Ill, p. 

 136, pl. 55, fig. 373. Pilsbry, Cat. Mar. Moll. Jap., p. 30. 



Buccinum trochulus. Reeve, Conch. Icon., sp. 7. 



Neptunea (Siphonalia) trochulus. Mart. u. Chom., Syst. Conch. Cab., Ill, pl. 3, p. 128, pl. 42, 

 figs. 2, 3. 



Our single specimen which is 38 millim. in height and 22 

 millim. in diameter is characterized by a short spire, a large and 

 ventricose body-whorl and spiral threads without any longitudinal 

 sculpture. The outer lip is thin and smooth within. But among 

 the specimens of the living shell, there are those with transverse 

 ribs within, in which case the lip is invariably more or less thick, 

 and the upper whorls more or less longitudinally plicate, so that 

 in these respects, the shell seems to be tolerably variable. 



Fossil occurrence. — Naganuma Zone (Naganuma). Tipper 

 Musashino of Shimosa and Kazusa, 



Living. — Central Japan. 



43. Siphonalia fuscolineata, Pease. 

 Pl. II. Fig. 15. 



Siphonalia fuscolineata. Pease, Proc. Zool. Soc. London, 1860, p. 189, pl. 51, fig. 3. Pilsbry, 

 Proc. Acad. Nat. Sei. Philadelphia, 1891, p. 473, pl. XIX, fig. 4. 



This is a species very closely allied to some forms of SipJtonali« 

 spadicea from which it could not be distinguished, if it were not 

 for the inner side of the thickened outer lip, which is transversely 

 and closely ribbed. Should this character not be enough for 

 specific distinction, then the two species must be united into one. 



A single specimen with eight whorls, 33 millim. in height 

 and 20 millim. in diameter. 



Fossil occurrence. — Naganuma Zone (Naganuma). 



Living. — Inland Sea (Western Japan) and Minoshima (in 

 Nagato) according to Adams. 



44. Siphonalia stearnsii, Pilsbry. 

 Pl. III. Figs. 3, 4 



Siphonalia Stearnsii. Pilsbry, Cat. Mar. Moll. Japan, p. 29, pl. IJ, figs. 1, 2. 



Several specimens which agree pretty well with the figures 

 and descriptions given by Pilsbry. Compared with Siphonalia 



