NO. 2124. TEE WEST AMERICAN SPECIES OF NUCELLA—DALL. 569 



Measurements. 



Whorls. 



Height 

 of shell. 



Height 

 of last 

 whorl. 



Height 

 of aper- 

 ture. 



Breadth. 



4J 

 4i 

 4J 



36.0 

 36.5 

 37.0 



28.0 

 25.0 



27.5 



THAIS CANALICULATA, new variety COMPRESSA. 



Monterey, California (60102). 



SheU similar to the typical form but with the elevated ridges or 

 major spirals flattened down until the interspaces become ahnost 

 linear. There are 6 or 7 on the penultimate whorl and 12 or 13 



on the last whorl. 



Measurements. 



THAIS (NUCELLA) EMARGLNATA Deshayes. 

 Plate 7^, figs. 1-3. 



? Purpura lagenaria Duclos, Ann. Sci. Nat., vol. 26, Mai, 1832, p. 112, pi. 2, fig. 



11; not of Lamarck, 1822. 

 ? Purpura rupestris Valenciennes, Voy. Venus, Atlas, 1846, pi. 9, fig. 1, a-h, 



(Magnified figure.) 

 Purpura emarginata Deshayes, Kev. Zool. Soc. Cuv., 1839, p. 360; Mag. de Zool. 



(Guerin), 1841, pi. 25. (Pathologic.) 

 Purpura lapillus var. anomala Middendorff, Beitr. Mai. Ross., vol. 2, 1849, 



p. 115, pi. 9, figs. 4, 5 (only). 

 Purpura emarginata Reeve, Conch. Icon., vol. 3, Purpura, 1846, pi. 10, fig. 46. — 



Cooke, Proc. Mai. Soc. London, vol. 11, 1915, p. 203. 

 Purpura conradi (Nuttall MS.) Reeve, Conch. Icon., vol. 3, 1846, in synonymy. 

 Purpura saxicola var. Carpenter, Rep. Brit. Assoc, for 1863, p. 662, 1864 



(Smithsonian reprint, 1872, p. 148). Not of Valenciennes. 

 Purpura ostrina Gould, U. S. Expl. Exped., Mollusca, 1852, p. 244; Atlas, 1857, 



pi. 18, figs. 310 a, b. Oregon. 

 Purpura saxicola Taylor, Trans. Roy. Soc. Canada, ser. 2, vol. 1, sect. 4, 1895, 



p. 72. Not of Valenciennes. 

 Thais emarginata Vanatta, Nautilus, vol. 24, No. 4, 1910, p. 37 (syn. exclus.). 

 Thais saxicola Keep, West Coast Shells, 1911, p. 179, fig. 168. 



Range. — Bering Island and the Okhotsk Sea on the west. On the 

 east Hagemeister Island and Bering Sea south of the winter floe- 

 line, and southeastward to California; Cerros Island, Lower Cah- 

 fornia; Mazatlan and Topolobampo, Mexico. 



