ASTRA LI I'M. 22% 



the umbilicus excavated, whitish, bounded by an intensely or :i! 

 verniillion tract. Alt, 28, diani. 40 mill. 



West Indies; Florida Keys (Simpson); Costa Rica; Yen* 

 T. '(urispigmentum Jonas is synonymous. 

 It is frequently larger than I have indicated. 



A. LATISPINA Phil., 1844. PI. 63, figs. 21, 22. 



Shell imperforate, conic, greenish, brown maculated ; whorls 7, 

 subplanate, obliquely costulate below the sutures, then with two 

 beaded spiral lirae ; margins of whorls exserted, expanded, com- 

 pressed, armed with triangular spines; last whorl sharply rarinate : 

 base radiately lamellose and ornamented with three or four ^numst- 

 concentric costse ; umbilical area depressed, pale greenish or yellow- 

 ish, aperture oblique, angulate. Alt. 35, diam. 50 mill. 



Gulf of Mexico to Rio Janeiro. 



Operculum oval, outside white, smooth, with a single arcuate 

 wide rib; inside flat, chestnut colored, nucleus submarginal. 



T. buschi Kiener, and T. tentorium Anton are synonym*. 



This form I have not satisfactorily identified with any shells I 

 have seen. It seems to be closely allied to the preceding species. 



Subgenus LITHOPOMA Gray, 1850. 



Shell turbinate or trochiform, elevated, imperforate, periphery 

 carinated or rounded, whorls above radiately plicate; operculum 

 oval, outside coarsely granulose, and either simply convex or with a 

 curved spiral rib with its terminations connected by a straight one ; 

 nucleus submarginal. West Indian Province. 



A. Turbinate species with rounded periphery. 

 A. TUBER Linn., 1767. PI. 56, figs. 79, 80. 



Shell turbinate-conic, imperforate, very solid, dirty white or pah- 

 green, radiately maculated with brown above, irregularly marked 

 and lighter below; whorls 6, upper two smooth by erosion, the fol- 

 lowing obliquely coarsely plicate and finely wrinkled in the same 

 direction above, somewhat shouldered, obtusely angular near per- 

 iphery, above which several obscure beaded lira? revolve, ehagreen- 

 ed by intersection of incremental stria? and oblique wrinkles: li- 

 nearly smooth ; aperture very oblique, oval, silvery within; colu- 

 mella short, wide, generally bituberculate at the base, excavated 

 over the location of the umbilicus. Alt. 45, diam. 50 mill. 



West Indian 7W/W ; 



