194 HELIX. 



rapidly increasing, the last rounded, slightly descending anteriorly ; 

 aperture rounded lunar, oblique ; columella well curved, expanded 

 over the umbilicus. Diam. 12-15, alt. 8-10 mill. 



St. lago, Cape Verdes, 



The present species differs from all the preceding in possessing 

 stronger spiral as well as incremental stria?. 

 H. MYRISTICA Shuttleworth, 1852. PL 52, figs. 61-63. 



Imperforate, depressed globose, shining, thin, brownish corneous 

 with four narrow brown bands, which are frequently interrupted 

 with light streaks and spots; sculpture as in H. visgeriana, com- 

 posed of incremental striaa and very numerous delicately impressed 

 spiral lines ; aperture rounded, the columella straighter than in H. 

 visgeriana; peristome thin, narrowly expanded, its columellar ter- 

 mination expanded and appressed over the umbilicus. 



Diam. 18, alt. 13 mill. St. lago. Cape Verdes. 



This species has not before been figured. I am not sure of the 

 relation it bears to If. fogoensis, (see above), but from the other 

 larger species of the Cape Verde group, advena and serta, the much 

 greater development of the spiral sculpture and the more globose 

 form will separate it. 



I am inclined to refer to this species as a variety, a form figured 

 on pi. 52, fig. 64. It is different in coloration, lacking the narrow 

 articulated brown bands of the type. Probably this is the H. ar- 

 joi (or arangoi) Dohrn, a form never described or figured, and re- 

 ferred by Pfeiffer to H. advena. My figure indicates that it is cari- 

 nated; this is not the case. 



H. BOLLEI Albers, 1854. PI. 51, figs. 53, 54. 



Imperforate, depressed., subglobose, thin, shining, subtranslucent, 

 brownish, corneous, finely obliquely striate and covered with an ex- 

 cessively minute granulation; spire low, sutures scarcely impressed ; 

 whorls 4i, slightly convex, rapidly increasing, the last carinated at 

 origin, the carina nearly disappearing toward the aperture, the base 

 convex and slightly indented in the centre, above descending a. lit- 

 tle anteriorly ; aperture oval lunar, oblique ; peristome labiate w r ith 

 white, its columellar termination deeply entering, the axis covered 

 by white callus. Diam. 11-13, alt. 7-8 mill. 



St. Vincente and St. Nicholas, Cape Verdes. 



Separated from all the preceding Cape Verdes species by the 

 sculpture. The fragile texture and keel stretched around the pe- 

 riphery are also peculiar. 



