1917.1 NATURAL SCIENCES OF PHILADELPHIA. 329 



somewhat fluted distally, though not often so much as in fig. 2. 

 The flat upper valve is generally smooth except for the usual rough 

 growth-lines. Both have crenulated inner edges when young, as 

 shown in the figures, but this feature is generally indistinct or lost 

 in old shells. The lower valve varies from having a rather deep 

 beak-cavity to none. A large specimen measures 14 cm. long, B 

 wide; others apparently adult are 10 cm. long. 

 Ostrea bryani n sp. PI. XX, figs. i. 2. 



Waianae, Oahu, from an excavation, about 20 ft. below the surface 

 of a reef elevated 60 to 80 ft. above sea level. Collected by Wm. 

 A. Bryan. 



The shell is very large, ponderous, oblong, extremely thick. The 

 more convex valve has a strong sculpture of rounded radial ridges, 

 some of which branch; at the lower edge there are about 15. Inside, 

 the beak occupies nearly half the total length. The flat valve has 

 a thin layer of calcareous material over most of the outside, but it 

 does not appear to be ribbed; towards the distal border, where it is 

 not encrusted, some coarse concentric laminae appear. Neither 

 valve shows any crenulation of the inner borders. 



Length of flat valve 210, width 140 mm. Weight of both valves 

 5 lbs. 9 oz. 



This huge oyster differs from 0. hyotis by its thick shell, long beaks 

 and far smaller corrugations. The associated shells are recent 

 species, so that the deposit is probably pleistocene. 



VII. VARIOUS GASTROPODS AND PELEOYPODS. 

 Strombus hawaiensis n. sp. PI. XXII, figs, i, 2. 



Pearl and Hermes Reef. Type collected by Lt. W. H. Munter. 

 Kauai at Haena and Milolii; Oahu at Paumalu and Waianae; and 

 INIolokai at Moomumi, all collected by W. A. and E. L. Bryan. 



The shell is turrited, speckled or mottled, and on the back of the 

 expanded lip banded with white. The last 4 or 5 whorls are angular 

 midway between sutures on the spire, and at the shoulder of the last 

 whorl. The earlier whorls are rounded. Nucleus smooth; three following 

 whorls having many low, narrow axial folds crossed by spiral threads; 

 on the subsequent whorls the folds weaken above the angle and become 

 nodular upon it; the slope above the angle becomes concave. On 

 the last two whorls the axial folds disappear and the nodules become 

 stronger. The spiral cords on the last whorl are strong and sub- 

 equal below the nodules, weak above them. A lump precedes the 

 anterior sinus of the outer lip. The lip expands, and is produced 



