128 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 



Shell much longer than O. cumingiana but with about the same 

 coloration, olive brown, glossy, streaked with narrow axial lines of burnt 

 umber; apex flatly obtuse, minutely and irregularly wrinkled; whorls 

 seven with suture slightly impressed ; aperture entirely without teeth 

 or plications of any kind ; outer margin thin, without callus ; columella, 

 slightly twisted; base imperforate. Length, 13 mm., diameter, 4 mm. 



Hypotype, no. 524 (Calif. Acad. Sci. type coll.) from Cocos Island 

 collected by W. H. Oschner, a member of the Expedition of the Cali- 

 fornia Academy of Sciences to the Galapagos Islands in 1905-1906. 



The specimen figured is the largest available specimen in our col- 

 lection and is 2^^ mm. longer than von Martens' type. Our other two 

 measure 9.5 and 10 mm. in length. These specimens were found among 

 a large series of O. cumingiana which passed through Dall's hands 

 without detection. 



The nuclear whorls appear to be identical with cumingiana and the 

 chief distinguishing features are the greater length and the lack of pli- 

 cations in the aperture. Although the species has not been illustrated 

 heretofore, von Martens' description seems to fit our shells so exactly 

 that we have confidence in the correctness of the identification. 



Leptinaria biolleyi von Martens 



Leptinaria biolleyi von Martens, Biol. Centrali-Americana, Moll., 

 June, 1898, p. 319, pi. 18, fig. 14. "Central Costa Rica: en- 

 virons of San Jose, 1135 metres above the sea, among moss 

 (Biolley)." "E. Costa Rica: Talamanca (Pittier, March, 

 1895)." von Martens, Sitz. Ges. Naturf. Freunde zu Ber- 

 lin, Jahrg. 1902, no. 3, p. 61. "in der Nahe von Wohnungen an 



der Bucht von Wafer, und nicht zahlreich." Biolley, Mol- 



lusques de L'lsla del Coco. Mus. Nac. de Costa Rica, 1907, p. 16. 



Wafer Bay, Cocos Island. Pilsbry, Manual Conch., ser. 



2, vol. 18, 1907, p. 316, pi. 41, fig. 18. Cocos Island. 



This species was described from Costa Rica by von Martens. Its 

 presence on Cocos Island (not numerous and found in the vicinity of 

 the habitation at Wafer Bay) led von Martens to suspect that the 

 species may have been recently introduced on the island on vegetation 

 or by some other method. 



