348 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY, 



€AI.L,IOSTOi«A SwAixsoN. 

 Calliostoma iridium Dall. 



Plate 19, figure 5. 



Calliostoma iridium Dall, Proc. U. S. Nat. Mus., 1895, 18, p. 7 ; 1902, 24, p. 552, 

 pi. 39, fig. 3. 



U. S. S. " Albatross," station 3387, Gulf of Panama, in 127 fathoms, sand, bot- 

 tom temperature 56°.2 T. U. S. N. Mus. 122,957 ; and at station 3391, in 153 

 fathoms, mud, temperature 55°. 8 F. 



Color of the shell a waxy pink, the apex somewhat darker, with variable deli- 

 cate brown flammules and darker brown ones on the periphery of the last whorl. 

 The base is destitute of flammules and the pillar is white. In this, as in most 

 shells not from the littoral region, the delicate colors are more or less evanescent. 

 The nacre is very bright, especially when the sliell is wet, showing through the 

 translucent outer coat. The operculum is pale yellow, concave externally with 

 an entire edge and about a dozen whorls. 



TURCICUtA Dall. 



Turcicula Dall, Bull. Mus. Conip. ZoiJl., 1881, 9, p. 42; type, Margarita (Turcicula) 

 imperialis Dall, /. c. ; Ibid., June, 1889, 18, p. 376, pi. 22, figs. 1, la ; Pilsbry 

 in Tryon, Man. Conch., 1889, 11, pp. 14, 3-30 ; Dall, Bull. U. S. Nat. Mus., 

 1889, 12, p. 162, pi. 22, figs. 1, la; Locard, Exp. du Trav. et du Talisman, 

 Moll. Test., 1898, 2, p. 21. 



Bembix Watson, Journ. Linn. Soc. London, 1879, 14, p. 603 ; Type, B. aeola Wat 

 son, op. cit., p. 603; Challenger Rep., Gastropoda, 1886, p. 95, pi. 7, fig. 13; 

 Japan ; not Bemhir De Koninck, 1844. 



Batkybembix Crosse, Journ. de Conchy 1, 1893, 40, p. 288, new name for Bembix 

 Watson, not De Koninck (the number, ostensibly for July, 1892, did not 

 appear until March, 1893). 



Tills group, at first instituted as a subgenus of Margarita, is now generally 

 admitted to be of generic rank. It is not only represented by characteristic 

 species in the Atlantic, eastern Pacific and Japanese seas, but is also known 

 from the Tertiary of the Pacific Coast of North America, characteristic species 

 being known from the Eocene and Oligocene. 



The type species of Bembix Watson, not De Koninck, was established on a 

 comparatively young shell from Japanese seas, but the adult has recently been 

 figured by Schepman (Leyden Museum Notes, 1905, 25, p. 100, pi. 8, figs. 4, 5), 

 and the " Albatross," liaving dredged in Japanese waters a number of specimens 

 of tills species, of various ages, I was enabled, by the kind as.sistance of Mr. 

 Edgar A. Smith of the British Museum, to confirm the decision of Schepman 

 as to the identity of his shell with the adult B. aeola. 



The species of this group now recognized among recent shells arc as follows : 



