ANTILLEAN LEPTINARIA. 293 



peristome simple, the right margin acute, arched a little for- 

 ward; columellar margin shortly reflexed, spreading, basal 

 somewhat thickened. Columella intorted, strongly calloused- 

 truncate in the middle. Length 7, diam. 4, aperture 3 x 2.5 

 mm. (Shuttl.). 



Porto Rico: very rare at Humacao, under dead wood 

 (Blauner). 



Leptinaria stylodon SHUTTL., Diagn. neuer Moll., no. 6, p. 

 142, in Mittheil. naturforsch. Gres. in Bern, 1854, p. 50. 

 CROSSE, J. de C., 1892, p. 30. B. stylodon PPR., Monogr., iv, 

 451. 



"Related to B. monodon C. B. Ad., from which it differs 

 by the larger size, rather flattened, not convex whorls, the 

 more acute spire, more expanded columellar margin and 

 thicker columellar tooth" (Shuttl.). 



This form probably cannot be separated even varietally 

 from the Jamaican L. monodon. The supposed differences in- 

 dicated by Shuttleworth are of little importance. 



Var. OPALESCENS Shuttleworth. PI. 43, figs. 48, 49. 



Shell imperforate, oblong-conic, striatulate, pellucid-hya- 

 line, glossy. Spire with obtuse apex. Whorls 6, a little con- 

 vex, the last rotund, three-sevenths the total length; suture 

 quite deep. Aperture semioval; peristome simple, acute, the 

 right margin arching a little forward; columella arcuately 

 callous-intorted, towards the base obliquely strongly truncate, 

 with a somewhat impressed area outwardly. Length 5, diam. 

 2.5, aperture 2x1.25 mm. (Shuttl.). 



Porto Rico: San Juan, Ceiba and Humacao. 



L. opalescens SHUTTL., Diag. n. Moll., no. 6, p. 142, in 

 Mittheil. Bern, 1854, p. 50. Bulimus (?) o., PFR., Monogr., 

 iv, 452. 



Related to the preceding [L. stylodon] but quite distinct, 

 as noted above. Animal huff (Shuttl.). The specimen of L. 

 opalescens from San Juan, figured on my plate (fig. 48), is 

 practically identical with the imperforate form from Jamaica, 

 which I have found in the same lots with L. monodon. 



JAMAICAN FORM (pi. 43. fig. 49). Shell imperforate, 



