LAND SHELLS OF GENUS OBBA FROM MINDORO 351 



This subspecies recalls 0. I. campoensis, but it is much less elevated 

 and differs in having the inalleations on the base approaching the 

 umbilicus to a much lesser degree. 



OBBA LISTERI SMITHI, new subspecies 



Plate 89, Figure 5 



The shell is large, lenticular, and acutely keeled at the periphery 

 with a narrow umbilicus. The coloration of the unique type, which 

 is a dead specimen, is problematical. It is flesh-colored with an 

 interrupted median band of blotches on each turn. There is also a 

 narrow interrupted band on the basal surface, about one-third of the 

 distance between the periphery and the umbilicus. The nuclear 

 whorls are well rounded, marked by fine incremental lines and micro- 

 scopic spiral striatums. The postnuclear whorls are rather flattened 

 on the upper surface and decidedly keeled, the succeeding turns 

 failing below the keel. They are marked by retractively curved 

 incremental lines and spiral striations, which increase in size on the 

 turns, and on the last whorl behind the aperture become exceedingly 

 strongly incised. What there is of malleation on the upper surface 

 is very weakly expressed. The base is slightly convex, marked by 

 incremental lines and spiral striations, which are a little stronger 

 toward the periphery than toward the umbilicus, and are most 

 strongly developed immediately behind the aperture. The aperture 

 is oval, with the perisome expanded, thickened, and reflected to cover 

 about one-third of the umbilicus. 



Type.— The type, U.S.N.M. No. 256413, was collected by the 

 writer at Port Tilig, Lubang Island. It has 4.5 whorls, and measures : 

 Height, 12.5 mm ; greater diameter, 35.3 mm ; lesser diameter, 28.2 mm. 



Remarks. — This is one of the most aberrant members of the listeri 

 complex. Its exceedingly strong incised spiral lines behind the 

 aperture separate it from all the other members of the group. 



I take pleasure in naming this subspecies for Dr. Hugh M. Smith, 

 who was deputy commissioner of the United States Bureau of Fish- 

 eries and director of the United States Bureau of Fisheries Albatross 

 Expedition to the Philippine Islands. 



OBBA LISTERI RECURVATA (Mollendorff) 



Plate 89, Figures 3, 4 



1896. Obba listeri var. scalaris Elera, nom. nud., Catalogo sistematico de toda 



la fauna Filipinas, vol. 3, p. 522. 

 1S98. Obbina listeri recurvata Mollendorff, Abh. Naturf. Ges. Gorlitz, vol. 22, 



p. 86. 

 1898. Obbina listeri recurvata var. subscalaris Mollendorff, Abh. Naturf. Ges. 



Gorlitz, vol. 22, p. 86. 

 1905. Obbina listeri recurvata Mollendorff, Kobelt, and Winter, Semper's Reisen 



im Archipel der Philippinen, vol. 10, pt. 1, pp. 22-23, pi. 6, figs. 3, 4. 



