MARINE MOLLUSKS — MACGINITIE 179 



Table 5. — Ratios of measurements in several "species" of Liocyma 



Also, in a number of species, specimens from Plover Bay have char- 

 acteristics developed to a degree not shown by specimens of the same 

 species from other localities. Most specimens of L. becki do not show- 

 such great height in proportion to the length. 



One lot of 7 specimens of Liocyma (from Point Barrow) of various 

 sizes and with concentric sculpture varying from closely set to widely 

 spaced, including two with a combination of the two types of sculpture, 

 were sent to the museum in Copenhagen for comparison with the 

 European Liocyma. W. K. Ockelmann identified all the specimens 

 as L. fluctuosa. 



In view of the above findings, it is obvious that a thorough study of 

 the genus is indicated to determine if these various forms can actually 

 be separated into species or if they are merely variants of one species. 



Distribution: The Arctic Ocean southward to northern Japan 

 and eastward to Kodiak Island and Port Etches (long. 147° W.), 

 Alaska; in the Atlantic area southward to Nova Scotia and Massa- 

 chusetts ?; the White Sea, and Iceland. L. fluctuosa is a new name 

 in the Pacific-Arctic fauna. 



