196 Williamson — West American Mitridx. 



fered in toto from what lie had " always called M. orientalis Gray,=J/. 

 iiiaara Swains, from Peru and Chilian Coasts." That species called M. 

 chilensix by L. C. Kiener is admirably figured under the latter name by 

 Kiener Coq. A'iv., Mitra, tab. 10, figs. 28, 28o. That shell is larger and 

 broader than the Californian shell, smoother and more shining — the spiral 

 pitting microscopical, the shape of the mouth distinct, more eff"use, outer 

 lip and the whorl pinched in towards the center as in the Californian 

 species — plicfe of columella slightly more oblique."* Upon further com- 

 parison between J/. orii'ntaJ'ix {M. iitaam),six\d M. /(?«•, Professor Mel vill says 

 of the first named, that it corresponds " exactly with the plate in Sowerby's 

 Thesaurus Conchyliorum III, PI. 354 (Mitra) t.40, being a more incrassate, 

 uncouth shell than id;v and apparently smooth, uniformly black ; with a 

 lens, slight pitting is discernable. The form of the mouth is also quite 

 different from /V/<T."t He adds that English Conchologists " such as Mr. 

 G. B. Sowerby, Mr. Edgar A. Smith, Mr. Sykes, and Mr. Fulton all recog- 

 nize the specific differences between idie and iiumra {orientalis)." Dr. 

 Wm. H. Dall and Dr. Paul Bartsch also agree that, "The California species 

 is distinct and should retain the name M. id:e Mel v." J 



The fine example (Fig. 7) of Mitra from Peru, received, through the 

 courtesy of Professor Melvill,from Sowerby and Fulton, bears this label : 

 " Mitra orientalis Gray 1834 



— maura Swainson, 1835 



— chilensis Keiner, 1839." 



The whole question evidently resolves itself into this: Swainson's Mitra 

 maura has not been found upon the Californian Coast, and, Swainson's 

 Mitra maura, on account of priority, is now called M. orientalis.^ M. orient 

 alls is not found north of Cape St. Lucas, Lower California, and the geo- 

 graphical listing of this sjaecies is incorrect. While P. P. Carpenter lists 

 M. inuvra among the Upper California Fauna in his Report on Moll, of W. 

 Coast of N. Amer. in 1856,|| in the British Rep't for 1863, he has this note: 

 '' Mitra maura Swains. Nutt. = orientalis Gray =^ chilensis Gray, Kien. Very 

 dark and plain. Peru. Sand between rock 1. w. Cuming," in Carpen- 

 ter's Catalogue of Mazatlan Shells (1857) there is no mention of M. orientalis 

 {maura) in place there are Mitra lens Mawe, and tStngatella tristis Brod. Dr. 

 E. E. C. Stearns also lists M. lensand M. tristis among other Mitras but does 

 not include M. orientalis among the "Shells of tlie Tres Marias" (Proc. U. 

 S. Nat. Mus., Vol. XVII, pp. 139-204). 



Of Mitra id:e in regard to relationship with other black Mitras from West 

 Coast of U. S. A. and South America, Professor Melvill says : " lens, maura 

 (orientalis), caliginosa, fultoni, idseand others may have been derived from 

 a common ancestor." 



* Letter. 



t Letter. 



t Letter. 



Ji Of the name orientalis for this shell, Professor Melvill writes : " It is an unfortun- 

 ate name, certainly, being a shell of the Western, not the Eastern hemisphere and is 

 exactly in the same position, therefore, as Oi/prw {Tririu) madagascariennis, which, as every- 

 body knows, does luA occur anywhere near Madagascar." 



II Binney's Bibliography of N. Amer. (,'onchology. Vol. I, p. 300. 



