Williamson — West American Mitridse. 197 



Mitra fultoni E. A. Smith. 



Mitra fultoni Smith Descriptions of New Species of Shells from Mauritius 



and California (An. & Mag. Nat. Hist., p. 256, figured, March, 1892) ; 



Williamson, Some West Amer. Shells, etc. (Bull. S. Cal. Acad. Sciences, 



Vol. IV, No. 8) p. 123,1905. 



This shell, as well as Professor Melvill's, is described in a Latin note and 

 is figured very finely. The type is from Point Abreojos, Lower California. 

 Long. 39 mm. diani. 13 ; aperture 19^ long; 5 lat. 



Dr. Dall writes he has seen " none from north of San Diego." Lately 

 they appear to be very scarce at that place as Professor Kelsey says he has 

 found none there. 



In his description, Mr. E. A. Smith says: "This species is well charac- 

 terized by the punctate sulci ; the jmnctures falling in regular, longitudinal 

 rows, through which pass well-marked impressed lines of growth." This 

 character of punctate sulci is a very noticeable one ; the pitting wider and 

 deeper than in M. idse is a prominent feature. As compared with M. 

 orieutalis Gray, Mr. E. A. Smith says : "The whorls are more convex, the 

 epidermis blacker, and the fine sjiiral striae which adorn the surface of that 

 species are scarcely indicated in the present form." Professor Melvill 

 says: "The outer lip is more effuse than in M. idn'." Fred L. Button, 

 Esq., writes : " I have made a pencil sketch (for you) of my specimen of 

 Mitra fultoni which gives a fair idea of this species. It is brown, has quite 

 a shoulder below the suture and has a few indistinct revolving lines of 

 sculpture." The figure referred to is more shouldered than any I have 

 seen. While adult specimens of J/, idx and M. fultoni exhibit differentia- 

 tion the young of both species might indicate a common ancestry at no 

 very distant era. 



Of the animals, Mr. Henry Hemphill writes: "The animals of all the 

 Mitras found on the coast of Southern California, so far as I remember, are 

 white, whether we call.them all mawa or fultoni or id:v." This agrees with 

 d'Orbigny's note on tropical American species. 



Mitra lowei Dall. 



3Titm lowei Dall, Diagnoses of New Species* of Mollusks from the Santa 

 Barbara Channel, California (Proc. Biol. Soc, Wash., Vol. XII, pp. 171- 

 170, Dec. 31, 1903), Keep, W. Amer. Shells, 1904, p. 321. 



This shell, dredged near Avalon, Santa Catalina Island, Cal., by Herbert 

 N. Lowe, is described by Dr. Dall as belonging to a type of J\I. fulgurita 

 Reeve,t but of markedly different proportions. The nucleus is very dis- 

 tinct from that of the type of J/, fxtrhadensis, etc. " Tlie only specimen seen 

 is clearly immature, but it is not the young of any of the species known to 

 inhabit the coast and is sufficiently characteristic to be easily recognized." 

 Length 5.5 ; of last whorl 4.5 ; diam. 2.5 mm. 



This yellow-brown shell was dredged with other shells at a depth of 

 water from 40 to 60 fathoms. 



* In this paper Dr. Dall also describes Mitr-a dolorosa from the Gulf of Cal., but as this 

 article does not include Gulf species it could not be listed. 



t For geographical range of this species consult Dr. Dall's Marine Mollusks of S. 

 Eastern Coast (Bull. 37, U. S. Nat. Mus.) p. 110, 1889. 



