MARINE MOLLUSKS — MACGINITIE 137 



Genus Nodotoma Bartsch, 1941 

 Nodotoma impressa (Morch, 1869, ex Beck MS.) 



Plate 16, figures 14, 15 



Pleurotoma impressa Morch, 1869, p. 21. — Leche, 1878, p. 54, pi. 1, fig. 16. 

 Beta impressa Friele, 1886, vol. 3, p. 18, pi. 8, figs. 1, 2; pi. 10, fig. 9. 

 Nodotoma impressa Bartsch, 1941, p. 5, pi. 1, fig. 2. 



Three specimens were collected: 1 drilled shell (10.2 by 4.9 mm.) 

 from 216 feet; 1 living (8.2 by 4.2 mm.) from 295 feet (pi. 16, fig. 14); 

 and 1 living (9.9 by 4.8 mm.) from 477 feet (pi. 16, fig. 15). The 

 nucleus of the latter was worn but entire and some of the ribs were 

 partly eroded. The nucleus of the one from 295 feet was rather badly 

 worn and the ribs of the first two postnuclear whorls were also badly 

 eroded. 



Other material examined : Several specimens in the collection of 

 the U. S. National Museum. 



Distribution: Point Barrow and the Sea Horse Islands to Kodiak 

 Island; and Spitzbergen. Point Barrow is a new locality. 



Genus Raphitoma Bellardi, 1848 

 Raphitoma amoena ? G. O. Sars, 1878 



Plate 8, figure 8 



? Raphitoma amoena G. Sars, 1878, p. 220, pi. 17, figs. lOa-b.— Thorson, 1935a, p. 

 48, figs. 48-49. 



Six specimens were dredged: 1 (about 3 mm. long) at 184 feet; 3 

 (about 2.2, 2.3, and 2.7 mm.) at 216 feet; 1 (about 2 mm.) at 453 feet; 

 and 1 (about 2.5 mm.) at 741 feet. 



Discussion: The largest of these shells have 3 whorls and perhaps a 

 fraction of another whorl, including the nucleus. They have ver}'- 

 prominent, sharp, spiral folds (pi. 8, fig. 8) that are confined to the 

 periostracum — 2 folds on the last whorl and 1 on the next to the last. 

 As in some of the other small shells, the calcified portions have dis- 

 solved. 



Dr. Thorson, who examined some of these shells, believes that they 

 are either young bottom stages of Raphitoma amoena or of some other 

 species of Raphitoma. I do not have enough comparative material 

 to continue the study of this species. 



Distribution: Point Barrow ?; and (Thorson, 1944) eastern and 

 western Greenland, Jan Mayen, Spitzbergen, and Norway north of 

 Lofoten. 



