82 BULLETIN 192, UNITED STATES NATIONAL MUSEUM 



U.S.N.M. No. 403138 contains 183 specimens collected by Orcutt at 

 Aquin. 



U.S.N.M. No. 402479 contains 70 specimens collected by Orcutt be- 

 tween Vieux Bourg and Baie des Flamands. 



U.S.N.M. No. 40401 1 contains 9 specimens collected by Orcutt on 

 the road between Torbeck and L'Acul. 



U.S.N.M, No. 401932 contains 7 specimens collected by Orcutt on the 

 road between Les Cayes and Torbeck. 



U.S.N.M. No. 401783 contains 27 specimens collected by Orcutt at 

 Les Cayes. 



HISPANIPOMA, new genus 



Shell ovate, marked by axial riblets and spiral threads whose junction 

 forms weak nodules. Some of the axial ribs fuse to form tufts at the 

 summit; others merely become thickened into cusps. Base openly um- 

 bilicated, the umbilical wall always marked by spiral cords a little 

 stronger than those of the spire. Aperture oval; peristome simple. Oper- 

 culum heavily calcified with strong, retractively curved ribs, which do 

 not extend to the outer edge of the whorls of the basal chondroid plate 

 but leave a small channel between the turns. 



Type species: Cyclostoma quaternata l^amarck = Hispanipoma qiiater- 

 natum (Lamarck). 



HISPANIPOMA QUATERNATUM (Lamarck) 



Shell elongate-ovate, varying decidedly in size in the different sub- 

 species. The color ranges from unicolor flesh-color to pale rose ; the in- 

 terior of the aperture varies with the color of the exterior. The nuclear 

 whorls form a blunt apex consisting of 1.5 turns, which are strongly 

 rounded and microscopically granulose, with the last portion of the last 

 turn showing indications of the postnuclear sculpture. The postnuclear 

 whorls are well rounded, narrowly shouldered at the summit, marked 

 by numerous, rather closely spaced, rounded, somewhat retractively 

 slanting axial riblets, which vary in strength and spacing, heavier and 

 more distantly spaced ones being usually succeeded by narrower and 

 more closely spaced series ; the spaces separating them are rarely as 

 wide as the riblets. These riblets terminate either individually in little 

 expanded cusps, or several of them become fused to form a conspicuous 

 hollow denticle. The spiral sculpture consists of numerous slender, 

 weakly developed threads, which are best seen in the intercostal spaces 

 and which render their junction with the axial ribs weakly nodulose. 

 Suture moderately well constricted. Periphery inflated and well rounded. 

 Base moderately long, inflated, strongly rounded, narrowly openly um- 

 bilicated, and marked by the continuation of the axial and spiral threads. 

 The ribs and spiral threads are also present on the umbilical wall. The 

 last whorl is solute for a fraction of a turn. Aperture oval; peristome 



