MAKINE MOLLUSKS — MACGINITIE 157 



Suborder Dysodonta 



Family Mytilidae 



Genus Mytilus Linnaeus, 1758 



Mytilus edulis Linnaeus, 1758 



Mytihis edulis Linnaeus, 1758, ed. 10, p. 705.^ — Oldroyd, 1924, p. 66, pi. 27, fig. 4, 



On Aug. 10, 1948, one right valve 60.6 mm. long and 31.7 mm. high 

 was dredged at Eluitkak Pass, and on Oct. 1, 1949, a portion of a left 

 valve was found on shore. 



Other material examined : Numerous specimens from the western 

 Atlantic and the eastern Pacific. 



Discussion: The area under investigation was relatively small and 

 in no place was there a suitable habitat for such tidal-zone animals as 

 M. edulis. These shell fragments may have been transported by 

 floebergs or by currents. 



Distribution: World-wide in temperate waters; in the Pacific area 

 from the Arctic (lat. 74° N.) to Cerros Island (lat. 28° N.) (Dall, 1921; 

 Keen, 1937). Madsen (1949) gives the northern limit of this species 

 as lat. 71° N. at Greenland and as Novaya Zemlya off Europe. 



Genus Musculus Rodiug, 1798 

 Musculus niger (Gray, 1824) 



Plate 18, figure 6; Plate 21, figure 6 



Modiola nigra Gray, 1824, p. 244. 



Modiolaria nigra Jensen, 1912, p. 63.— Oidroyd, 1924, p. 74, pi. 39, fig. 9.— Mor- 

 ris, 1947, p. 25, pi. 12, fig. 5; 1952, p. 45, pi. 6, fig. 4. 

 Musculus niger obesus Dall, 1916, p. 405. 

 Musculus niger Abbott, 1954, p. 355, pi. 28g. 



The largest living specimen collected, 50 by 23.3 by 11.6 mm., was 

 cast ashore on Oct. 17, 1949. If entire, a broken valve taken at 

 Eluitkak Pass would have measured about 56 mm. long by 27.5 mm. 

 high. In addition to those listed below, several juvenile specimens 

 were dredged at 477 feet. 



Eighteen living specimens were dredged: 2 (10.1 and 11.2 mm. in 

 length) at Eluitkak Pass on Aug. 10, 1948; 4 (3.3, 8.2, 8.5, and 10.5 

 mm.) at Eluitkak Pass on Aug. 30, 1948; 2 (11.2 and 12.4 mm.) at 

 151 feet; 2 (10.1 and 11.2 mm.) and 1 (30.2 by 16.5 by 8.5 mm.) at 

 204 feet; 1 (7.2 mm.) at 213 feet; 1 (7.2 mm.) at 216 feet; 1 (7.3 mm.) at 

 217 feet; 1 (12.5 by 7.3 by 4.4 mm.) at 341 feet; 1 (9.8 mm.) at 477 

 feet; and 2 (8.3 and 31.5 mm.) at 741 feet. 



Other material examined: Over 30 specimens from localities 

 ranging from Bernard Harbor, Northwest Territories, Canada, and 

 from near the mouth of the Colville River to Point Barrow and Icy 



