120 TROCHOMORPHA. 



T. TONKINORUM Mabille. PL 30, figs. 17, 18, 19. 



Shell rather widely and perviously umbilicated ; subtrochiforrn, 

 very much depressed, rather thin but somewhat solid ; rufescent ; 

 rather rudely costulate-incised, and marked with some inconspicuous 

 spiral lines; spire slightly convex, slightly projecting; apex obtuse, 

 concolored. Whorls 6, convex-flattened, carinated, regularly widen- 

 ing, separated by a margined, impressed suture : the last whorl car- 

 mated, a little convex in the middle, toward the carina compressed, 

 beneath radiately striated and slightly convex, obtusely angled 

 around the umbilicus. Aperture oblique, small, ax-shaped ; mar- 

 gins remote ; peristome straight, acute. 



Alt. 3, greater diam. 13, lesser 12 mill. (Mab.) 



Tonquin- 



T. tonkinorum MAE., Moll. Tonk. diagn. p. 7, May 14, 1887; 

 Bull. Soc. Mai. Fr. iv, p. 97, t. 3, f. 1, 2, 3. 



T. INFANDA Semper. PI. 20, fig. 4. 



Shell narrowly umbilicated, depressed, regularly striated above, 

 marked with impressed lines beneath ; reddish-chestnut, begirt with 

 a tawny band at the periphery. Spire depressed-conic, apex obtuse. 

 Whorls 5-6, nearly flat, carinated, the last convex beneath, nearly 

 smooth. Aperture oblique, angulate-lunar ; peristome simple, acute, 

 the upper margin straight, columellar margin not thickened. 

 Alt. 5?, greater diam. 12, lesser 11 mill. (Semp.) 

 Digollorin, Palanan and Cordillera of Amberbuk, E. coast North 

 Luzon. 



T. infanda SEMP., Reisen, p. 117. HIDALGO, Journ. de Conch. 

 1887, p. 93, t. 3, f. 5 ; Obras Malacol. i, p. 114. 



Hidalgo considers this a color-variety of Tr. albocinda Pfr. 



T. LUTEOBRUNNEA Mollendorff. PI. 20, figs. 20, 21. 



This is the form figured by Hidalgo (Journ. Conch. 1887, p. 95, 

 t. 4, f. 2), as Tr. splendens Semp. It is from the Island Sibuyan, 

 Philippines. No diagnosis has been published. See Mild ft'. Land- 

 schn. Cebu, p. 213, foot of page, and Hidalgo, Obras Malacol. i, p. 

 116. 



T. LOOCENSIS Hidalgo. PI. 20, figs. 11, 12, 13. 



Shell very broadly umbilicated, very much depressed, discoidal, 

 very acutely carinated ; very thin ; pellucid, a little shining, scarcely 

 striatulate, corneous- brown, unicolored. Spire flattened, slightly 



