1902.] NATURAL SCIENCES OF PHILADELPHIA. 529 



Clausilia sieboldi Pfr. 



C. sieholdtii Pfr., Proc. Zool. Soc, 1848, p. Ill; Monographia Hel- 

 Viv., II, p. 1G5; Conchylien Cabinet, Clausilia, p. 100, PI. 11, figs. 

 10, 11. 



C. sieboldi Pfr., Monogr., VIII, p. 520. Kobelt, Fauna moll, extra- 

 mar. Jap., p. 73, PI. 9, fig. 1. 



A species collected by Siebold, and described by Pfeiffer as 

 corneous-brown, with 10 whorls, a deep, arcuate lunella, visible 

 outside through the shell, and one moderate palatal plica. The 

 type measures 18 mm. long, 4 Mide in the middle. 



Kobelt described and figured specimens taken by Dr. Rein at 

 Amakusa, and between Hiugo and Bugo HJungo ?). He gives 

 the color as " dunkel hornbraun." " Die Priucipalfalte ist klein, 

 htiufig gar nicht zu erkenuen, die iNIoudfalte ist klein oder breit, 

 fast gerade, von der Priucipalfalte getrennt, und schicht unten 

 einen Ast nach hinten ; die Gaumenfalteu fehlen oder es ist eine 

 ganz kleiue vorhandeu, welche mitder ^Nlondfalte zusammenhiingt." 



The relation of this form to the next is a matter for further 

 investigation, with more material than is at present available. 



Clausilia sieboldi var. diptyx iiov. PI. XXVIII, figs. 19, 20, 21. 



Shell fusiform or turreted, the greatest width being either near 

 the middle or at the last whorl ; the spire rapidly tapering above to 

 a rather small, acute apex, the outlines of the terminal portion 

 straight. Dark purple-brown, fading to pale or yellowish -brown 

 above. Surface glossy, sculptured with strong, close rib-striae, 

 narrower than their intervals. AVhorls 9^, convex, the last some- 

 what flattened laterally, convex beneath, showing a pale or yellow- 

 ish curved streak in the position of the lunella. Aperture ovate, 

 dark within ; peristome white, thickened within, rather widely 

 reflexed, continuous, a little excavated at the sinulus. Superior 

 lamella rather small, thin, and short, not reaching to the lip-edge; 

 widely separated from the spiral lamella, which is a half whorl 

 long, penetrating to the middle of the ventral side. Inferior 

 lamella subhorizontal, thin, not extending upon the expanded lip, 

 ascending in a wide spiral within, penetrating as deeply as the 

 superior lamella. Subcolumellar lamella very deeply immersed. 

 Principal plica about a third of a whorl long, latero-dorsal. Upper 

 and lower palatal plicae rather short, subjjarallel, the upper one 

 curved ; they are connected by a very low luuella, scarcely notice- 

 34 



