MARINE MOLLUSKS — MACGINITIE 107 



Greenland to the Gulf of St. Lawrence, but Thorson (1944) does not 

 list it from Greenland. 



Buccinum teniie Gray, 1839 



Plate 9, figures 8, 9 



Buccinum ttnue J. Gray, 1839, p. 128, pi. 36, fig. 19.— Morris, 1947, p. 150, pi. 36, 

 fig. 3; 1951, p. 196, pi. 36, fig. 3.— Abbott, 1954, p. 225, pi. 24u. 



Seven living specimens were taken from 7 stations from depths 

 ranging from 110 to 341 feet, only 2 of these coming from over 130 

 feet. One live specimen was washed ashore in September 1949, and 

 2 others were taken in April and May 1950 by means of baited screen 

 traps lowered through holes in the ice to depths of 80 and 64 feet, 

 respectively. 



Other material examined: Numerous specimens from localities 

 from Bernard Harbor, Icy Cape, and south to eastern Siberia, Kam- 

 chatka, the Pribilofs, the Aleutians, and British Columbia; also from 

 the Grand Banks, Newfoundland, Greenland, and Spitzbergen. 



Discussion: Typical B. tenue is sculptured by fine, more or less 

 evenly spaced spiral threads that are crossed by fine incremental 

 lines that lend a wavy appearance to the spiral threads and produce 

 an over-all pattern. The sutures are moderately constricted and the 

 whorls moderately convex. Broken or interrupted folds or plications 

 cross the whorls, and in the last whorl they tend to become weaker 

 beyond the periphery. The periostracum is absent as often as it is 

 present; it may be entirely absent in some younger specimens, and 

 may be nearly all retained in some large shells, but more often it is 

 present in patches only (pi. 9, fig. 9). 



Instead of becoming weak or obsolete beyond the periphery of the 

 last whorl, in some specimens the longitudinal plications continue 

 strongly to the canal. In some the plications on the spire and body 

 whorl are sparse and weak; in others they are numerous and strong. 

 In some the whorls are much more convex and the sutures much 

 more constricted than in others; this convexity is not associated with 

 number or strength of the axial plications. On the whole, the very 

 large specimens tend toward very convex whorls and constricted 

 sutures. The spiral threads vary in fineness and, although they are 

 never actually grouped into fascicles, one may be unusually close to 

 another, giving the appearance of a missing thread. Some shells 

 may be approximately twice as thick or heavy as others of the same 

 size. The spire may be much longer in proportion to the aperture 

 in some than in others. There seems to be no consistency in these 

 variations as related to locality. One shell from Point Barrow has 

 more inflated whorls and deeper sutures than the others, while another 



473771—59 * 



