292 ANTILLEAN LEPTINARIA. 



shouldered, with a well-impressed suture ; last whorl large 

 and wide, sometimes a little constricted near the aperture, 

 which is rather wide, ovate, moderately acute above; labrum 

 thin and sharp ; columella straight, with an oblique tooth near 

 its extremity; umbilicus very small. Mean divergence 45; 

 length .25 inch; breadth .15 inch; length of aperture .13 

 inch" (Adams). 



Jamaica (C. B. Ad.). Constant Spring, St. Andrew 

 (Gloyne). 



Bulimus monodon C. B. AD., Contributions to Conchology, 

 no. 2, p. 28 (Oct., 1849). PFR., Monogr., iii, 389. GLOYNE, 

 Journ. de Conchyl., 1875, p. 119. Nameless in REEVE, Conch. 

 Icon., v, Bulimus, pi. 84, f. 119. 



Adams type lot contains some imperforate shells besides the 

 true monodon. Two of his largest individuals of the latter 

 are figured, figs. 41, 42, measuring- 

 Length 8, diam. 4, aperture 4 mm., whorls 6y 2 . 



Length 7, diam. 3.9, aperture 3.2 mm., whorls barely 6. 



The shell is pale buff-corneous, or bluish-corneous on the 

 back of the last whorl ; umbilicate, striatulate, with sharper 

 striae below the suture, about as in L. pallida. The spire is 

 decidedly stouter than in L. pallida, its sides diverging at 

 about 45 to 50 degrees; it appears somewhat gradate or ter- 

 raced, the sutures being narrowly and deeply impressed. The 

 last part of the last whorl is flattened above, often with a 

 slight groove on the flattened surface parallel to the suture. 

 The outer lip arches slightly forward. Columella short, white, 

 very strongly truncate obliquely. 



This species is very closely related to L. pallida, and may 

 prove to intergrade with that, but typically it is stouter in 

 figure, with the spire shorter and more broadly conic, and it 

 has a more strongly truncate columella. It also attains to 

 greater size, and is typically more openly perforate. 



PORTO Rico FORM. L. stylodon Shuttleworth. Shell min- 

 utely, falsely perforate, ovate-conic, very finely arcuately 

 striate, pellucid, waxen. Spire rather acute ; whorls 6, some- 

 what flattened, the last wide, flattened, three-sevenths the 

 total length ; suture rather deep. Aperture subauriform ; 



