114 PROCEEDINGS OF THE NATIONAL MUSEUM vol.70 



Family BATHYSCIADIIDAE 

 Genus BATHYSCIADIUM Dautzenberg and Fischer 



? BATHYSCIADIUM CONCENTRICUM, new species 



Shell minute, yellowish white, conic, circular at the margin, the apex 

 central, the sides slightly convex, sculptured with obvious concentric 

 lines; there is no other sculpture; the margin is simple, the interior 

 polished; height, 1.2; diameter, 2.5; length, 2.5 mm. U. S. Nat. 

 Mus. Cat. No. 329353. 



Off Georgia, one specimen. 



This little shell has the shape and aspect of a BatJiysciadium, though 

 there is no radial sculpture and in the absence of the soft parts it is 

 not possible to be certain of the genus. 



Family SIPHONARIIDAE 



Genus WILLIAMIA Monterosato 



WILLIAMIA, species 



A young specimen of this pelagic SipJionaria was obtained off 

 Georgia, but too immature for specific identification. It lives on 

 floating seaweed and reaches the sea bottom only after death. 



Family ISCHNOCHITONIDAE 



Genus ISCHNOCHITON Gray 



ISCHNOCHITON STRIOLATUS Gray 



Chiton striolatus Gray, Spicil. ZooL, p. 6, 1828. — Reeve, Conch. Icon., Chiton, 



pi. 22, fig. 144, 1847. 

 Chiton squamulosus C. B. Adams, Proc. Boston Soc. Nat. Hist., vol. 2, 



p. 8, 1845. 

 Ischnochiton striolatus Pilsbry, Tryon, Man. Conch., vol. 14, p. 105, pi. 20, 



figs. 20-24, 1892. 



Off Fernandina, three separated valves (U. S. Nat. Mus. Cat. No. 

 108159) which appear to belong to this species. St. Thomas, Bar- 

 bados, and Jamaica, according to Pilsbry. 



