66 BULLETIN 181, UNITEO SIT'ATEiS NlATT'ONlAiL MUSEUM 



CROCIDOPOMA (CROCIDOPOMA) MILLERI, new speciea 

 Pirate 12, Figubes 1-3 



Shell helicoid, covered with a pale brown periostracum, or at least 

 one would be led to believe so by the fragments clinging to the speci- 

 men at hand. Nuclear whorls about 1.6, well rounded, smooth. Post- 

 nuclear whorls inflated, very strongly rounded, marked by rather 

 slender, rather broad, spiral cords, of which 11 are present on the 

 last two turns between summit and suture. These are separated by 

 spaces only a little wider than the cords. The one at the summit is 

 broader than the rest and the space between the summit and this is 

 deeply inbent to form a wide channel at the suture. Periphery 

 strongly rounded. Base inflated, strongly rounded, marked by 10 

 spiral cords which equal those of the spire in strength and spacing. 

 Umbilicus moderately broad, the umbilical wall of the last whorl 

 bears 6 spiral cords. Aperture circular ; peristome rendered slightly 

 sinuous by the spiral cords, slightly notched at the heavy cord near 

 the summit. Operculum? 



The type, U.S.N.M. No. 389796, has 3.7 whorls remaining and 

 measures : Height, 7.0 mm. ; greater diameter, 9.9 mm. ; lesser diame- 

 ter, 7.4 mm. It was collected by Gerrit S. Miller on the slope of 

 Loma de Cielo, Bohoruco Mountains, at an altitude of 3,000 feet, 

 Polo, Barahona District, Dominican Republic. 



CROCIDOPOMA (CROCIDOPOMA) ORCUTTI, new species 



Plate 12, Figubes 36-38 



Shell large for the genus, depressed-helicoid, covered by a pale yel- 

 lowish periostracum. Nuclear whorls 1.5, well rounded, smooth. 

 Postnuclear whorls inflated, strongly rounded, marked by moderately 

 elevated spiral cords, of which 8 are present on the first, 10 on the sec- 

 ond, and 16 on the last part of the last turn between summit and peri- 

 phery. These cords increase in number by intercalation and therefore 

 vary considerably in strength. The first one near the summit, how- 

 ever, is always stronger than the rest. In addition to this the shell is 

 marked by rather strong incremental lines, which are more or less 

 hairlike and give to the spiral cords an almost granular aspect. Suture 

 profoundly narrowly channeled. Periphery well rounded. Base 

 strongly rounded, moderately broadly umbilicated, marked by 9 spiral 

 cords between which finer threads are present at the termination of the 

 last whorl. The umbilical wall bears 6 spiral cords with an inter- 

 calated one between the outer heavy keels. Last whorl solute for 

 about one-twentieth of a turn. Aperture slightly oblique, almost cir- 

 cular, with a slight notch formed by the subsutural keel; peristome 

 smooth. Operculum typically crocidopomid. 



