LEPTOTHYRA. 'Jf)!l 



Operculum (pi. 60, fig. 65) inside yellowish, multispiral, nucleus 

 Somewhat excentric ; outside calcareous, white, concentrically coarsi- 

 ly striate and radiately marked, except on margin of increment, 

 which is smooth and elevated; center subconcave and coarsely gran- 

 ulose. 



The synonyms are T. costulosus&owb., T. eo^fote* ("Gld") Sowb., 

 and Trochus (Gibbula) supra granosus E. A. Smith. 



A well marked form, of wide distribution, of which I have before 

 me many examples, all agreeing in the peculiar operculum. I can- 

 not follow Sowerby's synonymy in this group; he seems to have unit- 

 ed species from a mere superficial likeness. Here, as in the typi- 

 cal Turbo and Astralium, the characters derived from the opercula 

 are of high specific value, and this organ should be examined before 

 uniting the numerous described species. 



L. N ANINA Sowerbie, 1864. PL 58, figs. 55, 56. 



Shell minute, umbilicate, suborbicular ; apex obtuse; spirally im- 

 pressed-striate ; apex, subsutural tract and base with impressed ra- 

 diating stria 4 ; white, marked around the periphery with rosy equal- 

 ly spaced spots; whorls 5, convex; aperture rounded; columella 

 thickened ; umbilicus narrow, deep, rounded, radiately plicate on 

 the edge. Alt. 3, diam. 3 mill. 



Ins. Art, Archipelago of N. Caledonia. 



Evidently closely allied to L. Iceta. Operculum unknown. 



L. GRANULOSA Pease, 1868. PL 57, fig. 59. 



Shell small, solid, umbilicate, depressed orbicular, spire but slight- 

 ly exserted, very obtuse ; whorls 4, the first planorboid, upper ones 

 granulose, the last spirally lirate, the lirse about 25 in number, un- 

 equal ; aperture subcircular, deflected above ; umbilicus plicate 

 within ; color whitish, painted with broad radiating stripes and 

 spots of reddish brown ; white around the umbilicus. 



Alt. 3 2, diam. 4 mill. 



Ins. Pomi]x . 



The spire is usually slightly shorter than in the figure. 



The aperture does not show the minute lirre within its outer mar- 

 gin, and teeth within the base which are found in 7>. hvtn, and is 

 smaller and more oblique than in L. pilala. 



L. FLUCTUATA Hutton, 1884. PL 64, figs. 47, 48. 



Shell small, rather solid, spirally striated, not iridescent; color 

 yellowish white or pale brownish, with irregular waved longitudinal 



