58 BULLETESr 181, UNITEB STATES NATIONiAL MUSEUM 



which are quite regular, are a little more than twice as wide. Periphery 

 rendered almost angulated by a spiral cord. In addition to the spiral 

 cords the whorls are marked by slender incremental lines. Suture well 

 impressed. Base rather short, well rounded, marked by the continua- 

 tion of the incremental lines and 9 spiral cords, which equal those on 

 the spire in strength, but weaken toward the aperture. The umbilical 

 wall also shows traces of spiral cords. The umbilicus is about one- 

 fifth the greater diameter of the last whorl. Aperture oblique ; peri- 

 stome simple. Operculum typically amphicyclotulid. 



The type, U.S.N.M. No. 535857, comes from Long Dilton, Dominica. 

 It has 4.5 whorls and measures : Height, 5.5 mm. ; greater diameter, 

 8.0 mm.; lesser diameter, 7.2 mm. A paratype is in the Americam 

 Museum of Natural History. 



This species is nearest related to A, (A.) schraTmni (Shuttleworth), 

 from which it can be distinguished readily by its color and the greater 

 number of spiral cords. 



AMPHICYCLOTULUS (AMPHICYCLOTULUS) LIRATUS (Drouet) 



Plate 11, Figxjees 4-6 



1859. Cyclophorus Uratns Dkouet, Essai sur les mollusques terrestres et fluviatiles 

 de la Guyane frangaise, p. 88, pi. 3, figs. 30-32. 



Shell decidedly depressed-helicoid, openly umbilicated, covered by a 

 wax-colored periostracum. Nuclear whorls 1.3, well rounded. Post- 

 nuclear whorls strongly rounded, marked by rather strong, regular and 

 regularly spaced spiral cords, of which 14 are present between the 

 summit and the suture on the last turn. In addition to the spiral 

 sculpture, the whorls are marked by closely spaced incremental threads. 

 Suture well impressed. Periphery well rounded. Base moderately in- 

 flated, well rounded, marked by 18 spiral threads, which equal those 

 on the spire in strength, and by the continuation of the incremental 

 lines. The umbilicus is about one-fourth the width of the greater 

 diameter of the shell, and the umbilical wall bears a few indications of 

 spiral threads. A cross section of the last whorl would appear broadly 

 oval. Aperture slightly oblique, circular, with scarcely any angling at 

 the posterior angle of the aperture; peristome simple. Operculum 

 typically amphicyclotulid. 



The specimen described and figured, U.S.N.M. No. 474037, comes 

 from Martinique. It has 4.4 whorls and measures : Height, 7.3 mm. ; 

 greater diameter, 14.2 mm. ; lesser diameter, 10.3 mm. 



This species suggests both A. (A.) mineri and A. (A.) guadeloupen- 

 sis but differs from them in having the spiral sculpture extend to the 

 peristome and in being much more depressed. 



