12 BUIJLETIN 192, UNITED STATES NATIONAL MUSEUM 



the inner a little less expanded and reflected; the outer extends but 

 slightly beyond the inner. Operculum thin, paucispiral, with almost sub- 

 marginal nucleus the outside covered with a very thin deposit of fine 

 calcareous granules. 



U.S.N.M. No. 1 5 1329 contains 3 specimens collected by Salle in the 

 Dominican Republic. They are probably topotypes. The one described 

 and figured has a little more than 4 whorls remaining and measures : 

 Length, 8.5 mm. ; greater diameter, 4.7 mm. ; lesser diameter, 3.8 mm. 



U.S.N.M. No. 493312 contains 3 specimens received from H. C. 

 Fulton labeled "Haiti." 



U.S.N.M. No. 315178 contains 3 specimens from the Evezard Col- 

 lection. 



CHONDBOPOMA (CHONDBOPOMOBUS) OI.SSONI PUsbry 



Plate 1, Figure 4 



1933. Chondropoma olssoni Pilsbry, Proc. Acad. Nat. Sci. Philadelphia, vol. 85, 

 p. 125, pi. 6, figs. 1-4. 



Complete shell elongate-turrited ; when truncated, very elongate-ovate, 

 almost subcylindric, of buff or pale brown ground color, variously banded 

 with dark brown. In the type there are four bands of somewhat varying 

 width between the summit and the periphery and one below the periph- 

 ery. In other individuals the subperipheral only is indicated, while 

 others vary between these two extremes. Nuclear whorls 2, small, in- 

 flated, well rounded, smooth. The postnuclear whorls are moderately 

 inflated, crossed by low, rounded, retractively curved axial riblets, 

 which are separated by mere impressed lines; two, three, or four of 

 these riblets become fused into tufts at the summit of the turns where 

 they form strong, almost white denticles. These denticles are also rather 

 variable in width and spacing. In the type they are rather broad. The 

 spiral sculpture also consists of threads, which equal the axial riblets 

 in strength but are a little more widely spaced. The junctions of the 

 axial riblets and spiral threads do not produce pronounced tubercles, 

 while the spaces between them suggest thimble-pitting. The suture is 

 well constricted, rendered wavy by the denticles; periphery somewhat 

 inflated, well rounded. The base is moderately long, inflated, well 

 rounded, openly umbilicated, and marked by the same type of sculpture 

 as the spire. The last whorl is solute for one-fourth of a turn with a 

 conspicuous carina at posterior angle. Aperture broadly oval; peristome 

 simple. Operculum thin, corneous, paucispiral, with submarginal nucleus. 



The type (Acad. Nat. Sci. Phila. No, 160978) has almost 4 whorls 

 remaining and measures : Length, 14.3 mm. ; greater diameter, 7 mm. ; 

 lesser diameter, 5.9 mm. It was collected by A, A. Olsson on Cerro 

 Monte Cristi, Dominican Republic. 



U.S.N.M. No. 426046 contains 8 topotypes received from the Academy 

 of Natural Sciences of Philadelphia, 



