136 BULLETIN 192, UNITED STATES NATIONAL MUSEUM 



the summit, and marked by slender, retractively curved axial riblets, of 

 which 200 are present on the last whorl in the specimen figured. These 

 riblets become expanded into slight auricles at the summit, which they 

 minutely denticulate. Suture rather strongly channeled. Periphery in- 

 flated, strongly rounded. Base moderately long, openly umbilicated, and 

 marked by the continuation of the axial ribs, which extend over the 

 umbilical wall. The latter bears 14 rather strong spiral threads, which 

 render the axial riblets slightly scalloped. The last whorl is solute for 

 about one-tenth of a turn. Aperture oval; peristome double, the outer 

 very narrowly expanded, a little broader at the junction of the basal 

 and inner Hp and also at the posterior angle where it forms a slight 

 auricle. At the parietal wall and the posterior portion of the outer lip 

 it is very narrow; the outer peristome is marked by concentric lines of 

 growth; the inner peristome is strongly exserted and reflected, wider 

 than the outer on the outer lip. Operculum with very strong lamellar, 

 retractively curved ribs, which on the inner half of the turns become 

 fused at their outer edge but still maintain their individuality. On the 

 outer half they are decidedly distinct, but the extreme outer edge again 

 becomes fused. This gives to the lamellation of the operculum a sort of 

 3-stage appearance, a narrow separate channel between the turns, a 

 pseudolamella on the inner half and distinct lamellation on the outer half. 



The specimen figured (U.S.N.M. No. 504067) is one received from 

 Cuming from the Dominican Republic. It has 5.5 whorls remaining and 

 measures: Height, 27.3 mm.; greater diameter 17.3 mm.; lesser diame- 

 ter, 14.8 mm. 



A second specimen (U.S.N.M. No. 529453) was received from Ful- 

 ton, and a third (U.S.N.M. No. 504068) was collected by Dr. Abbott 

 in the Barahona District. All three of these are without operculum. 

 The operculum that I have described is from Dr. Pilsbry's specimens 

 collected at Mr. Hermann's coffee finca on a hill beyond Paradis, a 

 town on the coast south of Barahona, Dominican Republic. 



Subgenus Eccritopoma Pilsbry 

 1933. Eccritopoma Pilsbry, Proc. Acad. Nat. Sci. Philadelphia, vol. 85, p. 128. 



Clydonopomas of turbinid outline and having a few spiral threads 

 near the summit of the turns in addition to those of the umbilical wall. 



Type species : Parachondria peasei Pilsbry = Clydonopoma (Eccrito- 

 poma) peasei (Pilsbry), 



CLYDONOPOMA (ECCBITOPOMA) P£AS£I (Pilsbry) 



Plate 21, Figure 2 



1933. Parachondria (Eccritopoma) peasei Pilsbry, Proc. Acad. Nat. Sci. Philadel- 

 phia, vol. 85, pp. 128-129, pi. 6, figs. 5-7. 



Shell of turbinid outline, thin, with the extreme nuclear tip white, the 

 three succeeding whorls brown and the rest pale yellow, marked bv 



