52 STROBILOPS, S. G. ENTEROPLAX. 



16. Strobilops polyptychia (Mlldff.)- PI- 12, figs. 14, 15, 16. 

 Shell openly umbilicate, diseoidal, closely costulate above, 



striatulate beneath, browoi. Spire slightly raised ; whorls 51/0 

 to 6, nearly flat, the last subacutely angular at the periphery 

 and somewhat so around the umbilicus. Aperture diagonal, 

 obliquely heart-shaped, the peristome continuous, free, ex- 

 panded, a little reflected and thickened within ; parietal margin 

 deeply sinuate. Two parietal lamellse, one extending to the 

 edge of the peristome, the other falling a little short of it, 

 both penetrating inward to the middle of the whorl. Nine or 

 ten short palatal lamellae situated at the third part of the last 

 whorl. Height II/4, greater diam. 314, lesser 3 mm. (Mlldff.). 

 Cebu : peak of Mount Licos (Moellendorff ) . 



Pledopylis polyptychia Moellendorff, Jahrb. D. Malak. 

 Ges. XIV, 1887, p. 272, pi. 8, f. 8-8c.; Abh. d. naturf. Ges. 

 Gorlitz, 1897, p. 147. — Gude, Science Gossip, IV, September, 

 1897, p. 102, fig. 55a-d. 



The parietal and infraparietal lamellae enter fully a half 

 whorl; between, above and below their inner ends is a low 

 white callus forming somewhat triangular lobes with inwardly 

 directed angles in the intervals, its surface only weakly gran- 

 ular. The edges of the parietal lamellae appear under a high 

 power to be smooth and rounded. The ten basal folds within 

 the last third of the last whorl are short, slightly unequal, and 

 form a close series from the foot of the columellar wall to the 

 periphery. Two specimens measure: 



Height 1.8, diam. 4.3 mm. ; 5% whorls ; umbilicus contained 

 2% times in diameter. 



Height 1.5 diam. 4 mm., o^/^ whorls; umbilicus contained 

 about 3 times in diameter. 



It is much lower than other species, with a more broadly 

 open umbilicus and more numerous baso-palatal folds (fig.l4). 



17. Strobilops trochospira (Mlldif.). PI. 11, figs. 5a-c, 6a-e. 



Shell openly and perspectively umbilicate, depressed-conoid, 

 costulate above, striatulate below, corneous, with conoidal 

 spire. Six slightly convex whorls, the last rather acutely 



