HISPANIOLAN AND BAHAMAN ANNULARIIDAE 169 



U.S.N.M. No, 5041 3 1 contains a topotype from the same source. 



U.S.N.M. No. 393788 contains 2 specimens taken by Bartsch 15 miles 

 north of Gonaives. 



U.S.N.M. No. 393803 contains 4 specimens taken by Bartsch at Peter- 

 borough Mountain, north of Ennery. 



This species resembles Troschelvindex abbotti, but can easily be dis- 

 tinguished from it by not having the broadly expanded outer peristome. 



CHRISTOPHIPOMA, new genus 



Shell of ovoid outline. The postnuclear w^horls are marked by axial 

 ribs, which are of two strengths, the interval between the strong ribs 

 bearing several finer threads. Spiral sculpture on the spire is indicated 

 by a few series of feeble nodules. The umbilical wall, however, bears 

 strong spiral cords. Aperture circular, with the inner peristome very 

 strongly exserted, and the outer very decidedly expanded. Operculum 

 with subcentral nucleus, bearing a broadly obliquely extended, thin 

 lamella, which does not extend to the outer edge of the turns of the 

 chondroid basal plate. The lamella is marked by retractively curved, 

 slender threads. 



Type species : Chondropoma bertini Maltzan = Christophipoma bertini 

 (Maltzan). 



The shells of this genus somewhat resemble Lugarenia of Cuba, from 

 which they differ in having the aperture circular, inner peristome de- 

 cidedly exserted, and the outer broadly expanded. The opercular lamella 

 here also is oblique instead of flattened to parallel the chondroid basal 

 plate. 



CHRISTOPHIPOMA BERTINI (Maltzan) 



Shell elongate-ovate, flesh-colored, marked with spots of brown, 

 which are arranged in both axial and spiral series ; the outer peristome 

 is rayed. Nuclear whorls almost 2, well rounded, smooth, forming a 

 rather small apex. Postnuclear whorls inflated, narrowly channeled at 

 the summit, marked by lamellar axial riblets between which finer axial 

 threads are present. This differentiation between the stronger and lesser 

 axial ribs is not so pronounced on the last whorl. There are several 

 lines of nodules on the ribs near the summit. Suture strongly con- 

 stricted, rendered crenulated by the axial riblets. Periphery inflated, 

 strongly rounded. Base moderately long, openly umbilicated and marked 

 by the continuation of the axial ribs. On the umbilical wall spiral threads 

 are present, which are rendered weakly nodulose by the axial ribs. Last 

 whorl solute. Aperture subcircular ; peristome double, the inner strongly 

 exserted ; the outer broadly, flaringly expanded. Operculum with almost 

 central nucleus and a strongly elevated, decidedly oblique lamella, 

 which is marked by feeble, retractively curved threads. 



The species comes from northern Haiti, where it breaks up into two 

 races as follows : 



