CUBAN ANNUDARiroAE TORRE AND BARTSCH 217 



and within the iimbiHciis by 13 very fine slender spiral tlireads. 

 Aperture almost circular; peristome double, the outer broadly 

 expanded on the inner hp, a little less expanded on the parietal wall, 

 where it is adnate to the preceding turn, and least expanded on the 

 outer lip, notched at the posterior angle to form the breathing siphon; 

 inner peristome scarcely at all exserted but broadly reflected. Oper- 

 culum paucispiral, opisthosiphonid. 



The type, U.S.N.M. No. 314941, came from the mouth of Cueva 

 del Circulo, near El Cercado, Sierra de Cubitas, Camagiiey Province. 

 It has 3.5 whorls remaining and measures: Length, 12.5 mm.; greater 

 diameter, 11.5 mm.; lesser diameter, 8.8 mm. 



The species ranges from the type locahty slightly westward into 

 the pass kno\vn as Vereda de los Burro. 



XENOPOMOIDES, new genus 



Shell elongate-conic; axial sculpture consisting of decidedly elevated 

 spinose lamellar ribs, between which less elevated threads are present. 

 Spiral sculpture merely indicated by the regular position of the spines 

 or scallops on the spire and base. Aperture subcircular with double 

 peristome, the outer broadly expanded, notched on the middle of the 

 inner lip, with the part posterior to the notch reflected over and clos- 

 ing the umbilicus. Operculum opistliosiphonid, or like the young of 

 Xenojwma. Breathing pore present at the posterior angle of the 

 aperture, a little behind the peristome. 



Type: Xenopomoides delicatulum, new species. 



XENOPOMOIDES DELICATULUM. new species 



Plate 19, Figure 1 



Shell elongate-conic, thin, milk white. Nuclear whorls 2, decidedly 

 inflated, strongly rounded, microscopically granulose, forming a large 

 mamm.illated apex, which projects over the precedmg turn. Post- 

 nuclear whorls strongly rounded, marked by axial ribs, which are of 

 two series, one decidedly lamellar and distantly, not regularly spaced; 

 the other series more numerous, between the lamellar ribs consisting 

 of elements a little higher than threads, yet not quite lamellar. The 

 elevated ribs are provided at regular intervals with scalloped, flattened, 

 denticle-like projections, which are not hollow; of these, 5 occur 

 betv/een the summit and suture and 3 on the base between the edge 

 of the closed umbilicus and the periphery. Suture strongly con- 

 stricted. Base short, strongly rounded. Aperture subcircular; 

 peristome double, the inner slightly exserted and slightly reflected; 

 the outer very broadly expanded and notched on the edge of the inner 

 lip, the portion posterior to the notch being reflected over the um- 



