501 MAZA.TLAN UNIVALVE9 



interstitiis concavis ; lirulis spiralihus promineniihus, costis 

 superantibus ; canaU aperturcB longHudine subaquante. 



Only one dead specimen was found of this pretty little 

 species, whicli somewhat resembles in extreme miniature the 

 F. Dupetit-Thouarsii, quoted from the Galapagos, Cuminff, and, 

 (though on the authority of Kiener only,) from Mazatlan. 

 Long, "le, long. spir. '08, lat. "07, div. dO". 

 Sab. — Mazatlan ; 1 sp. off Chama ; L'pool Col. 



Tablet 2413 contains the specimen. 



641. FustJS APEETUS n. s. 



F. t. subelongatd, albidd, mfo-fusco irregulariter fasciatA ; 

 anfr. nucleosis ii. tumentibus, irregularibus ; normalibus iii. 

 + . . . hand valde tumentibus, suturti impressd ; costis radiantibus 

 circitef xi\. rotiindatis, hand valde prominentihus, basin versus 

 obsoletis ; interstitiis parvis ; lirulis spir alibus, costis superan- 

 tibus ; canali aperto, parum recurvato, longitvdine aperturcB 

 curtiore. 



The six specimens found of this species were either young 

 or fragmentary ; tlie size of the nucleus betokening a much 

 larger shell. It diflers from F. tumens in the spire being less 

 elevated, the whirls and ribs (which are more numerous) less 

 swollen, and the canal shorter and open. A perfect young sp., 

 •with 5 whirls, measures long. "1, long. spir. '047, lat. '055, 

 div. 40°. 



Sab. — ]\Iazatlan ; extremely rare, off Spondylus and Chama ; 



Upool Col. 



Tablet 2414 contains 2 young sp. and a fragment of one older. 



642. PFtTsus , sp. ind. (a.) 



Tablet 2415 contains a minute shell, with 2 large irregular 

 nuclear whirls, and a normal whirl, finely cancellated, white, 

 of a subconoid shape. 



Sab. — Mazatlan ; 1 sp. off Spondylus ; L'pool Col. 



643. PFrsxJS , sp. ind. (b.) 



Tablet 2416 contains a minute transparent shell of 3 whirls, 

 of which the first two arc swollen and irregular, the third sub- 



