339 



Sculpture consisting of axial striae which begin just beyond the embryonic 

 whorl and continue as far as the edge of the peristome. On the last whorl 

 these lines cross the periphery and continue to the columella. Suture slightly 

 impressed especially at the embryonic and nepionic whorls, and at the body 

 whorl it is paralleled by a supersutural depression which continues onward 

 above the periphery as far as the peristome. Periphery sharply keeled. 



Embryonic whorl high and abruptly merging into later whorls. Body 

 whorl somewhat rounded above periphery, but rather flat at the base, and 

 slightly descending at aperture. Peristome expanded with area of depression 

 behind it. Columella flat, slanting outwards and forming a definite angle 

 at the juncture with the base of the peristome. Though imperforate, there 

 is a depression at the umbilical region, which is quite well defined. 



Alt. Diam. Ap. Height Ap. Width 



9 12.5 4.5 5 mm. Holotype, M. C. Z. no. 79176 



9 12.5 4.5 5 Paratype, M. C. Z. no. 47227 



8.5 12 4.5 5 " " " " 



8.5 12 4 5 



Holotype.— M. C. Z. no. 79176. Paratypes:— M. C. Z. no. 47227. Lubang 

 Island, Pedro de Mesa, collector, 1929. 



Remarks. — There are two Philippine species that are more or 

 less closely allied to this one. These are H. acuta Sby. and 

 H. acutissima Sby. H. ignava differs from H. acuta in being 

 higher spired and in possessing an umbilical depression. It 

 differs from H. acutissima in having a solid yellow color and in 

 not possessing a subsutural band of color. Two specimens in 

 the Museum of Comparative Zoology collection from Agcalatao, 

 Tablas, are very close to this form, but differ sufficiently in 

 minor detail to be held subspecifically distinct. These are a 

 little smaller and the umbilical depression is much less developed. 

 For this subspecies we propose the name Helicina ignava tabla- 

 sensis. 



