100 THE NAUTILUS. 



by a very thin callus ; the outer margin at first rather straight, 

 scarcely reflexed, then carved, basal margin nearly straight, 

 reflexed. Umbilical margin dilated, thickened, slightly cover- 

 ing the umbilicus. Diam. 21 to 29, alt. 7| to 8 mm. Same 

 localities (Same reference). 



The description of this species applies very well to H. lohrii 

 Gabb. I think it a synonym of that species. 



Helix inveda J. Mabille. Depressed-orbiculate, without cuticle 

 or color, but with traces of a brownish line above ; solid, rather 

 thick, coarsely striatulate and under a lens beautifully striatu- 

 late. Whorls 4, the last angular at periphery, rather swollen 

 below, at the aperture dilated and slightly descending. Peris- 

 tome expanded, slightly thickened, the approaching margins 

 joined by a rather thick callus ; columellar margin dilated in a 

 triangular plate over the umbilicus. Diam. 21, alt. 7 mm. 

 Lower California (same reference, p. 65). 



Seems nearer S. lohrii than any other species I have seen. 



Helix digueti J. Mabille. Subdepressed, without color or cut- 

 icle, solid, subopaque, irregularly and densely costulate-striate, 

 apex nearly smooth, whorls 4, the last slightly dilated and 

 shortly descending to the aperture. Peristome reflexed, margins 

 joined by a very thin callous, columellar margin dilated, nearly 

 covering the umbilicus. Diam. 20 to 20|, alt. 8 to 9 mm. 

 No locality mentioned (same reference, p. 65). 



I have seen no species answering to the description of this. 



Group of S. hachitana. 

 SoNORELLA MERRiLLi Bartsch (1904). Below San Quentin, L. 



Cal. 



The surface has "very dense, exceedingly minute granula- 

 tions, both on the upper and the lower surface." Height 12.5, 

 diam. 22, umbilicus about 4 mm. 



SONORELLA PENINSULARIS n. Sp. PI. 2, flgS. 4. 



The shell is umbilicate (the width of umbilicus contained 

 between eight and nine times in the diameter of the shell), 

 moderately depressed, the spire low-conic ; pale cinnamon with 

 a few white streaks, having a chestnut-brown band above the 

 periphery, margined narrowly with whitish above, more wideh* 

 below ; whitish around the umbilicus. The surface is glossy, 

 lightly marked with growth-lines, and in some places above the 



