HELIX-LUCERNA. 115 



ery of the whorl a short distance behind the aperture. The two 

 outer teeth are much united at their bases; and there is often an 

 accessory denticle between the inner and the second tooth. 



Nearly always imperforate, rather globose, strong, opaque, shin- 

 ing, dark-brown, apex and a peripheral fascia generally white, base 

 usually lighter ; surface minutely, densely granulate ; spire low 

 dome-shaped, apex planulate, polished, sutures impressed ; whorls 4? 

 to 5, convex, very gradually widening ; body-whorl subdepressed, 

 rounded at the periphery, often with an obsolete peripheral carina, 

 deeply deflexed at the aperture, deeply scrobiculate behind the pe- 

 ristome, the furrows rather longer than in H. simson. Aperture 

 subhorizontal, transverse, somewhat wedj^e-shaped ; peristome flesh- 

 colored, broadly expanded, basal margin reflexed, adnate over the 

 umbilicus, bearing within four lamellar entering teeth, the outer one 

 at its inward extremity strongly bent outward, the middle two enter- 

 ing obliquely toward the axis, the inner tooth smallest, not directed 

 toward the axis, separated from the second tooth by a broader space 

 than the spaces separating the remainder of the teeth, this space some- 

 times bearing a small denticle in the middle ; two outer teeth not 

 united at their bases ; terminations of peristome united by a parie- 

 tal callous, continued from the upper margin of the peristome. 



Alt. 16, diarn. 27 mill. 



Jamaica. 



H. sinuata MULLER (" Hist. Verm, ii, p. 18, 1773 "), PFEIFFER, 

 Monographia, i, p. 305 (excl. varr.) ; Conchyl. Cab. p. 79, t. 10, f. 

 5, 6. (teste Pfr.), t. 153, f. 5 ; I.e. p. 445. REEVE, f. 243. IT. pro- 

 penuda AD. Contrib. to Conch, no. 5, p. 79. PFR. Monogr. iii, p. 212. 



Note the passages above italicized. There is great variation in 

 dimensions and degree of depression. Umbilicus is rarely partly 

 open. The smallest specimen before me measures, alt. 12, diam. 21 

 mill. 



Var. PROPENUDA Ad. 



Shell likeH. sinuata, but the color is very pale, almost white ex- 

 cept on the upper whorls ; aperture more contracted ; the exterior 

 furrows are very short, and the right pair of teeth a little joined at 

 base. Imperforate. (Ad.*) Quite a distinct color variety. 



H. SINUOSA Ferussac. PI. 27, figs. 76-79 ; pi. 38, figs. 76-79. 



More depressed than H. sinuata, umbilicate ; the outer tooth of 

 aperture not flaring outward at its inner extremity, or only slightly 



