MARINE MOLLXJSKS — MACGINITIE 141 



Discussion: In his study of the northern species of this genus, 

 Lemche (1948) found that the species Usted in the synonymy above 

 all belong to the species C. occulta, in which he recognized two varieties : 

 occulta and scalpta, the latter being broader than var. occulta. He 

 also described a new species, C. magna, specimens of which had been 

 identified under some of the above names. He found that C. occulta 

 and its varieties are found in shallow water, and C. magna in deeper 

 water. 



In the specimens that I examined, the sheUs of hving specimens 

 range from creamy white to brown, and from those with a closed 

 umbihcus (pi. 4, fig. 3) to those with an open umbihcus. 



Distribution: Point Barrow to the Aleutians; Greenland to 

 Maine; and (Lemche, 1948) Iceland, Spitzbergen, Finmarken, the 

 Murman Coast, the White Sea, and north of Siberia. 



Family Pyramidellidae 



Genus Odostomia Fleming, 1813 

 Odostomia cassandra Dall and Bartsch, 1913 



Plate 8, figures 5, 6 

 Odostomia cassandra Dall and Bartsch, 1913, p. 142, pi. 10, fig. 2. 



Seven specimens were dredged: 1 (2.8 mm. or more long, with 4 

 whorls) from 140 feet on Aug. 21, 1948; 1 (1.9 mm., with 3.5 whorls) 

 from 216 feet; 2 (1.4 mm., with 3 whorls; and 1.6 mm., with 3 whorls) 

 from 453 feet; and 2 (1.4 mm., with 2.5 whorls; and 2 mm., with 3 

 whorls) from 741 feet. In addition, there is a specimen from 741 feet 

 in which the shell was completely dissolved by the preservative. The 

 animal is about 3.2 mm. long and 2 mm. in diameter, and a yellow 

 operculum is present. 



Other material examined: The type from the Queen Charlotte 

 Islands. (Only 1 other specimen, the cotype, has been recorded.) 



Discussion: In these shells the aperture is as long as or longer than 

 the remainder of the shell; there is no sculpturing except fine, silky 

 lines of growth. At first these shells were opaque and white, with a 

 silky sheen, but in alcohol they have become hyaline. The type, 

 which is somewhat larger than the largest specimen (with a shell) 

 from Point Barrow, is not highly calcified and appears somewhat 

 hyaline in spots. 



Distribution: Point Barrow and Skidegate, Queen Charlotte 

 Islands, British Columbia. The Point Barrow specimens extend the 

 range from the 55th to beyond the 71st parallel of latitude. 



