MAHINE MOLLUSKS — MACGINITIE 93 



specimen that measured 28 mm. long, 18 mm. wide, and 14 mm. high 

 is 17 mm. long and 12 mm. wide. 



In life, the general color of these animals was tan to brown on a 

 dusky white background. Fine, chalk-white dots were scattered over 

 the background, and there was an occasional larger, pale lemon dot 

 that looked like an aggregation of small dots. Fine lines of brown ex- 

 tended up the tubercles along the ridges. There were ridges and con- 

 volutions around the outer edge of the foot, and in each groove there 

 was a fine line of tan. 



Distribution: The Kara Sea, Novaya Zemlya, the Murman 

 Coast, Finmarken, Spitzbergen, Hope Island, Bear Island, Iceland, 

 and Greenland (Thorson, 1944). It is new to North America and the 

 Pacific area of the Arctic. 



Onchidiopsis groenlandica Bergh, 1853 



Variety 



Onchidiopsis groenlandica Bergh, 1853, p. 346, pi. 2. — Odhner, 1913, pp. 12, 74, 



pi. 2, figs. 19, 25; pi. 5, figs. 1, 6. 

 Onchidiopsis groenlandica Bergh var. pacifica Bergh, 1887, p. 278, pi. X, figs. 18, 



22; pi. Y, fig. 19; pi. Z, fig. 23.— Odhner, 1913, p. 75. 



A single specimen of what apparently belonged to this species was 

 washed ashore in July 1948, but it was subsequently lost. The entire 

 notaeum was bright orange and much smoother than that of 0. glaci- 

 alis. In its semicontracted state, the animal was about 27 nmi. long. 



Distribution: Odhner (1913) gives the distribution as follows: 

 Spitzbergen, Norwegian Islands, in the stomachs of cod; western 

 Greenland, Grinnell Land, Iceland; and the var. pacifica Bergh from 

 Kyska Harbor in the Aleutians. It is new to the Alaskan Arctic 



Genus Pilisciis Loven, 1859 

 Piliscus commodus (Middendorflf, 1851) 



Plate 5, figures 4r-6 



Pilidium commodum Middendorflf, 1849d, p. 427 (no description); 1851, p. 214, 



pi. 17, figs. 4r-ll. 

 Pilidium radiatum G. Sars, 1878, p. 144, pi. 8, figs. 6a-d. 



Eighty-five specimens, with shells ranging from 5 to 26 mm. in 

 length, were collected. One washed ashore during a storm in Sep- 

 tember 1949, and seven during a storm in August 1950; the snails 

 were still intact in their shells but most of them had died from exposure 

 on shore and several of the shells were broken. One was dredged at 

 Eluitkak Pass (40 feet), where the bottom is stony. The remaining 

 76 specimens were dredged at depths ranging from 120 (1 specimen) to 

 453 feet. The greatest number, 43, from any one haul was secured 



