LAURIA, SUBGENUS LEIOSTYLA. 73 



c Outlines of spire but slightly convex ; aperture produced 

 o , J towards the outer-basal part. L. cheilogona, no. 26 



] Outlines of spire strongly convex; aperture not so pro- 

 ^ duced (35) 



C Spire convexly conic ; length 3 to 3.5 mm. 



L. vincta, no. 27 

 Spire thick in the upper part ; length 4.4 mm. 



L. v. watsoniana, no. 27a 



35 I 



(Canary Island Species.) 



Shell broadly ovate, the diam. 60 to 65 per cent of the 

 length; chestnut above, the base pale; angular 

 lamella not distinctly connected with the lip-inser- 

 tion. L. castanea, no. 48 



Shell narrower, oblong, the diam. 52 to 57 per cent of 

 the length; angular lamella connected by a callus 

 with the lip -insertion (37) 



Chestnut above, the base pale ; rather finely striate. 

 gy I L. pythiella, no. 49 



Banded with chestnut on a pale ground; weakly plica- 

 tulate. L. tceniata, no. 50 



(Azores Islands Species.) 



( Aperture with a small angular lamella continued inward 

 as a thread, the columellar lamella small or im- 



38 1 mersed ; no parietal or palatal teeth. 



L. fasciolata, no. 51 

 (^ Three to six teeth present (39) 



8 to 9 nearly flat whorls; aperture somewhat trilobed; 



39 .| two lamellae on the columella. L. tesselata, no. 55 

 6 or fewer whorls (40) 



Angular lamella connected with the lip-insertion; pari- 

 etal lamella moderately developed (41) 

 . Angular lamella large, widely separated from the lip- 

 insertion, the parietal lamella very small or sub- 

 obsolete; shell ovate, irregularly, coarsely ribbed. 



L. vermiculosa, no. 54 



