338 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 53. 



mal, increasing regularly in diameter; the altitude of the body 

 whorl one-third that of the entire shell. Suture simple above, 

 afterward keeled by the preceding whorl. Aperture quadrate; the 

 margms simple; the left lip somewhat reflected. Alt., 0.0027; diam., 

 0.0011. 



"It is in honor to the memory of the learned Commodore Rang 

 that we have given his name to this odd species of CTiemnitzia and 

 we feel a considerable satisfaction in being able thus to give witness 

 to our feelings of profound esteem for a leader under whose orders 

 we have served, as well as to express our admiration for his high 

 scholarship. This shell is somewhat elongate, yellowish in color, 

 tending a little toward a brown. Tlie apex is rather obtuse. The 

 spire is made up of 12 whorls, all of them smooth. The sides of 

 the early whorls are almost straight, and this part of the shell is 

 regularly conic. The four or five later whorls differ from the first 

 anteriorly in that they escape from the profile of the cone and widen 

 on a plane with the base, thus forming a prominent keel, which is 

 very thin, almost sharp edged, upon the periphery. This expansion 

 of the base follows the whorls of the spire, mcreasmg in prominence 

 as they increase in diameter. Thus the keel terminates on the right 

 margin of the aperture. The suture is extremely narrow, and on 

 the whorls furnished with the keel which we have just described 

 it occurs in front of the keel, between the keel and the succeeding 

 whorl. The aperture is ahnost quadrate; the margins are simple, 

 and the left margin is slightly reflected upon the columella. 

 "Type locality. — Negritos, or Margarita Island, Panama." 

 I have not seen specimens of this species, and quote the description 

 and figure. 



SCALENOSTOMA BABYLONIA Bartsch. 



Plate 45, fig. 2. 



Odostomia (Scalenostoma) babylonia Bartsch, Proc. U. S. Nat. Mus., vol. 42, 

 1912, p. 287, pi. 38, fig. 3. 



Shell elongate-conic, light yeUowish-brown, excepting the umbili- 

 cal area, the extreme basal portion, and tip, which are white. Nuclear 

 whorls very small. Postnuclear whorls flattened, separated by a 

 scarcely impressed suture. On the last three turns the whorls are 

 marked at the periphery by an exceedingly strong, acute, spiral 

 keel, which is slightly bent downward. Base of the last whorl 

 short, well rounded. Entire surface of spire and base smooth, 

 except for exceedingly fine, incremental lines. Aperture oval; pos- 

 terior angle acute; outer lip rendered } -shaped by the spiral keel; 

 inner lip slender, evenly curved, very slightly revolute; parietal wall 

 glazed with a thm callus. 



