THE CYOLOPHORiID LAI^D M0LLUSIK9 OF AMEKICA 189 



lar ribbed striations, chestnut brown with diffused, irregularly 

 distributed spots. The last whorl has a narrow yellowish line at 

 the peripheral angle and below this a somewhat broader darker zone, 

 which evanesces anteriorly. The whorls are comparatively small and 

 project but slightly, smooth, of pale color (injured in the single 

 specimen before us). There are 5.5 convex turns, of which the 

 earlier ones increase in size gradually, and the later ones more 

 rapidly. They are separated by a deep suture, which is channeled 

 in the later portion. The last whorl has a distinct angulation at 

 the periphery and is more strongly arched basally than on the upper 

 part and irregularly coarsely malleated. The last whorl is some- 

 what flattened near the suture. The posterior part of the peristome 

 of the outer lip is bent up to form a small hooklike auricle. I know 

 of none like it in any American operculate. Aperture very large, 

 only slightly oblique, irregularly tear-shaped, broadly rounded 

 basally, pointed toward the posterior angle, where it passes into the 

 auricle, bluish white within. The parietal wall is covered with a 

 half-moon-shaped slight callus. The outer peristome is sharp edged, 

 bent backward above and free from the preceding whorl so that a 

 deep sinus is created. It is bent upward above the periphery of 

 the preceding turn to form an auricle. The columellar peristome 

 is thickened and white and slightly effuse. The operculum, unfor- 

 tunately, is broken but there is enough of it to show that it is a 

 genuine Neocyclotus operculum, although it is not strongly thickened, 

 but it bears numerous whorls with a threadlike projection on the 

 inner edge of the turns. It is not impressed in the middle. 



Habitat: New Granada (Colombia). 



The specimen I received in the winter of 1872 to 1873 direct with 

 some other land shells. My friend Martens, to whom I showed the 

 shell, said that it was an over-developed example of Cyclotus in- 

 ccrniytus Sowerby, and under this name it has rested until now in 

 the Senckenbergische Museum. That species has also a sinus at the 

 posterior angle. 



Kobelt's figure shows a specimen not quite mature, which we believe 

 related to A. (/.) malleatum. Probably due to immaturity, the 

 siphonlike development at the posterior angle has not attained its 

 full figure. Kobelt's figure yields the following measurements: It 

 has 4.8 whorls and measures: Height, 26.3 mm.; greater diameter, 

 53.0 mm. ; lesser diameter, 37.3 mm. Height of aperture, 18.4 mm. ; 

 diameter, 22.8 mm. 



428349 — 42 13 



