[SCIENTIFIC RESULTS OF THE PHILIPPINE CRUISE OF THE FISHERIES STEAMER 

 "ALBATROSS," 1907-1910.— No. 27.] 



THE PHILIPPINE MOLLUSKS OF THE GENUS DIMYA. 



By Paul Bartsch, 



Assistant Curator, Division of Mollusks, United States National Museum. 



During the cruise of the United States Fisheries steamer Albatross 

 in the PhiUppines a number of mollusks belonging to the genus Dimya 

 were obtamed at several of the deep-sea stations which are here 

 described. 



Most of the known members of this genus are fossils, only two hav- 

 ing been described as now existing species. These are Dimya argentea 

 DaU^ from the West Indies and Dimya corrugata Hedley^ dredged 

 off New South Wales. 



To these two additional species are now added. 



DIMYA FILIPINA, new species. 

 Plate 28, figa. 1-4. 



Shell heavy, inequivalve, of variable outline, depending upon the 

 nature of the support to which the basal valve is attached. Outside 

 of upper valve brown, marked by strong closely spaced overlapping 

 concentric laminations which are free at their edges. These lamina- 

 tions are present on the prodissoconch and increase steadily in size 

 from this to the edge of the adult shell. Radiating sculpture entirely 

 wanting. In the lower valve which is much stronger than* the upper, 

 the laminations assume the form of moderately strong corrugations. 

 In this the external surface is marked with radiating zones of chestnut 

 brown which are about one-third as wide as the light area that sepa- 

 rates them. The interior of the shell is pale buff; the material of 

 this color forms a thin layer in the dorsal valve which readily flakes 

 away, exposing a chestnut colored basal layer. Resilium resting in a 

 strongly excavated pit in the dorsal valve, bendmg under a little shelf 



1 Bull. Mus. Comp. Zool., vol. 12, 1886, p.228. ^ Mem. Austr. Mus. Sydney, vol. 4, 1902, pp. 308-309. 



Proceedings U. S. National Museum, Vol. 45— No. 1983. 

 . 80459°— Proc.N.M.vol.45— 13 20 305 



