NO. 2124. THE WEST AMERICAN SPECIES OF NUCELLA—DALL. 571 

 THAIS EMARGINATA, new variety PROJECTA. 



Sitka, Alaska. 



Shell thiimer, more elongate and with a pointed spire, the major 



and minor spirals more nearly equal, two strong spirals on the earlier 



whorls and the sutures more constricted. This is the more northern 



form (88842). 



Measurements. 



THAIS (NUCELLA) FREYCINETII Deshayes. 



Purpura freydnetii Deshayes, Rev. Zool. Soc. Cuv., 1839, p. 360; Mag. de Zool. 



(Guerin), 1841, pi. 26. 

 Purpura freycineti Middendorff, Beitr. Mai. Ross., 1849, p. 117 (part); Sibir. 



Reise, vol. 2, pt. 1, ]851, p. 219, pi. 12, figs. 1-9. 

 Purpura freydnetii Reeve, Conch. Icon., vol. 3, Purpura, September, 1846, 



pi. 10, fig. 51.— ScHRENCK, Amurland Moll., 1867, p. 388. 

 Polytropa lapillus A. Adams, Ann. Mag. Nat. Hist., vol. 5, 1870, p. 423, not of 



Linnaeus. 

 Purpura freydnetii Lischke, Jap. Meeres Conch., vol. 2, 1871, p. 40, pi. 4, figs. 



15-19. 

 Purpura lapillus Dunker, Ind. Moll. Mar. Japan, 1882, p. 4, not of Linnaeus. — 



PiLSBRY (following Adams), Cat. Mus. Moll, of Japan, 1895, p. 45. 

 Purpura freydnetii var. alabaster Pilsbry, Proc. Acad. Nat. Sci. Phila., for 1907, 



p. 246, pi. 20, fig. 2. Chishima, Japan. 



Range. — Southern Kamchatka, the Kuril Islands, the south and 

 west coasts of the Okhotsk Sea, Sakhalin Island and Northern Japan 

 to Kushiro. 



The shell described and figured by Deshayes is immature, the com- 

 plete outer lip and labial caUus are not yet formed. It is further 

 exceptional in its feeble spiral sculpture and extremely low spire. 

 However, the peculiarities of the pillar lip and the general form 

 enable one to connect it with the common Japanese species with a 

 reasonable degree of probability. Smce the species goes through 

 practically Xho, same phases of variation as T. lima, and both are 

 present over part of their range, more or less confusion has resulted 

 in the literature either from a superficial examination or a paucity 

 of material. 



The variety alahaster has a certain analogy with the shorter heavy 

 forms of T. lameUosa, other mutations recall T. lima, but the most 

 common type of aU among the specimens I have been able to bring 

 together most resembles the rougher type of T. emarginata. If these 

 all belong to one species, the process of divergent evolution is less 

 complete in Japan than in America. 



