1905.] NATURAL SCIENCES OF PHILADELPHIA. 121 



Pecten awajiensis n. sp. 



Shell solid, equilateral, both valves moderately convex, the right 

 valve less so ; lower half semicircular, the upper half straightly tapering. 

 Convex valve dull purplish-white with purple-brown clouding and a few 

 small white spots in the furrows. The other valve is light brown with 

 some darker zones, and more white in the grooves. 



Ears large, the posterior slightly longer. Ribs 17, high and rounded, 

 and slightly wider than the intervals in the left valve, decidedly so in 

 the right, where their margins slightly overhang the intervals. Growth- 

 striae fine, close and inconspicuous. Ears finely costellate. Anterior 

 and posterior dorsal surfaces of the main disk flattened and smoothish. 

 Interior white and strongly grooved, calloused above the muscle scar. 

 Ctenolium short, of five teeth. 



Length 48.6, height 47, diam. 14.5 mm.; length of the hinge-line 

 33 mm. 



Fukura, Awaji. Type No. 88,300, A. N. S. P., from No. 1,636 of 

 Mr. Hirase's collection. 



This species is related to P. singapormus Sowb. (Thes. Conch., 1, PI, 

 14, fig. 71), from which it differs chiefly by the much coarser and less 

 numerous ribs. 17 instead of 23 or 24. The dorsal half of the shell is 

 also more wedge-shaped than in the Singapore scallop, of which a 

 topotype is before me. 



Reference to Plates II, III, IV and V. 



Plate II, Fig. 1. — Conus aratispira n. sp. 

 Figs. 2, 3. — Eulima ogasawarana n. sp. 

 Fig. 4. — Conus voluviinalis aims n. subsp. 

 Fig. 5. — Xatica hirasei n. sp., exterior of operculum. 

 Fig. 6. — Natica hirasei n. sp., shell. 



Figs. 7, S. — Eulima luchuana Pils. Ivikai-ga-shima, Osumi. 

 Figs. 9, 10. — Eulima bovicornu n. sp. 

 Fig. 11. — Eulima articuJata Sowb. Hahajima, Ogasawara. 



Plate III, Fig. 12. — Siphonalia vanattai n. sp. 



Fig. 13. — Maculotriton hracteatus longns Pils. and Van. 

 Fig. 14. — Usilla gouldii Smith. Hahajima, Ogasawara. 

 Figs. 15, 16, 17. Torinia densegranosa n. sp. 

 Figs. IS, 19. — Planaxis ahhreviata ogasawarana n. subsp. 

 Fig. 20. — Buccininn chishimanum Pils. 



Plate IV, Figs. 21, 22.— Eihalia guamensis sanguinea n. subsp. 

 Fig. 23. — ColumbeUa pardalina subcribraria n. subsp. 

 Figs. 24, 25, 26. — Ethaliella floccata Sowb. Topotype. 

 Fig. 27, 28. — Ethalia guamensis selenomphala n. subsp. 

 Figs. 29, 30. — Phorcus borealis n. sp. 

 Fig. 31. — Cingula kurilensis n. sp. 



