THE CTCLOPHORID LAND MOLLUSKS OF AMEIRIOA 99 



almost vertical axial ridges, which are separated by spaces about 

 twice as wide as the ridges. Beginning with the third postnuclear 

 whorl, the ridges assume a protractively slanting position. Here 

 they do not reach to the summit but terminate at the anterior third 

 between summit and suture. These ridges here are not quite so wide 

 as the spaces that separate them. On the last whorl they again dis- 

 appear and the whorl is marked by irregular nodules, which become 

 decidedly enfeebled on the last portion of this turn. Suture strongly 

 impressed on all but the last turn, which is adnate to the preceding 

 whorl. Periphery well rounded. Base strongly rounded, openly, 

 rather narrowly umbilicated and provided with a rather strong keel 

 at the outer limit of the umbilicus. The base is marked by lines of 

 growth and scarcely any indications of nodulations. The umbilical 

 wall is marked by rather rough lines of growth. Aperture circular, 

 protracted into an angle at the posterior angle. Operculum typically 

 ptychocochlid. 



The type, U.S.N.M. No. 356025, is one of a large series of speci- 

 mens collected by Henderson at Savanna la Mar, Westmoreland 

 Parish, Jamaica. It has 4.5 whorls and measures : Height, 13.0 mm. ; 

 greater diameter, 20.2 mm. ; lesser diameter, 14.5 mm. 



This species is confined to the region about Savanna la Mar, that 

 is, the southern side of central Westmoreland Parish. 



PTYCHOCOCHLIS ORCUTTI, new species 



Plate 15, Figubes 27-29 



Shell large, helicoid, covered with a chestnut-brown periostracum, 

 sometimes with a light zone near the summit and the periphery. 

 When the periostracum is removed there is a pinkish tinge to the 

 shell substance of the last whorl. The nucleus consists of 1.5 well- 

 rounded, smooth whorls. The postnuclear whorls are inflated and 

 strongly rounded ; the first is marked by feeble, slightly retractively 

 slanting, hairlike riblets, which are not so wide as the spaces that 

 separate them. Beginning with the second postnuclear whorls, weak, 

 oblique, low, protractively slanting ridges make their appearance, 

 which do not reach the anterior fourth between summit and suture. 

 These disappear shortly after the last whorl is reached, where they 

 are replaced by feeble, irregular nodules, which become obsolete on 

 the last part of the last turn. Suture moderately strongly impressed 

 on the early whorls ; the last has the summit appressed, which char- 

 acteristic renders the sutrure less conspicuous. Periphery well 

 rounded. Base somewhat inflated, well rounded, openly, moder- 

 ately broadly umbilicated. The umbilicus is bounded on the out- 

 side by a cord, which is rendered rough by the incremental lines. 



