HYPSELOSTOMA. 183 



Loochoo Is.: Yonakunijima (Y. Hirase). Type 95,252 A. 

 N. S. P. 



Hypselostoma insularum PILS., The Conchological Maga- 

 zine, ii, 1808, p. 41, fig. 2. 



This species resembles H. luzonicum Mlldff., from near 

 Manila, in shape. It differs by the much smaller size, shorter 

 neck, the presence of a subcolumellar (or it may possibly be 

 a basal) fold, and the more sinuous angulo-parietal tooth of 

 the Loochoo species. The very fine and delicate spiral striae 

 seem to be of cuticular substance. 



Philippine Species. 

 6. HYPSELOSTOMA LUZONICUM Moellendorff. PL 32, figs, 7, 8, 9. 



Shell narrowly perforate, thin, corneous-brown. Whorls 

 5%, angulate-convex, separated by a deeply impressed suture, 

 striatulate, the upper ones angular below the middle, forming 

 a turrited-conic spire, the last whorl flattened, having a slight 

 spiral sulcus over the basal carina, free almost from the 

 middle, built out a long way, somewhat ascending. Crested 

 at suture and periphery, around the umbilicus and on the 

 back, so that it is somewhat tetragonal, at the base distinctly 

 lineolate spirally. Aperture turned upward very little, 

 rounded-quadrangular, with 4 or rarely 5 teeth opposed 

 cross-like; parietal lamella strong, high, entering deeply, 

 somewhat flexuous; columellar smaller, horizontal, receding; 

 two or three teeth in the throat. Peristome simple, thin, a 

 little expanding. Alt. 2%, width 2%, alt. and width of aper- 

 ture 1mm. (Mlldff.). 



Philippines : Antipolo, province of Manila, Luzon, on lime- 

 stone. 



Hypselostoma luzonicum MLLDFF., Nachrbl. d. Mai. Ges., 

 1888, p. 145 ; Bericht Senckenberg. Ges., 1890, p. 250, pi. 9, 

 f. 1 ; with var. major, p. 250, pi. 9, f. 2, and var. imbricata, 

 p. 250, pi. 9, f. 3. 



The angular lamella is wholly concrescent with the parietal, 

 but its inner end, where it joins the parietal, is very slightly 

 deflected towards the periphery. The upper palatal converges 

 inward towards the lower, and a smaller interpalatal stands 



