440 MAZATLAN TJKIVALVES 



a brownisli white. In a genus the species of which present so 

 few peculiarities, it is not thought prudent to describe it. It 

 seems to have nine whirls, and measures long. '115, long. spir. 

 •075, lat. -045, div. 23°. 



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



553. ? Leiosteaca , sp. ind. (b.) 



Tablet 2024 contains a short stuupy shell ; with the apex 

 decollated. It appears to have been brown, and displays a 

 continuous peritreme. It bears some resemblance to the 

 AV. Indian L. fulvocincta, C B. Ad. Contr. Conch, no. 7, p. 111. 

 It has four whirls, and measures '077 by '035. 



Hah — llazatlan ; 1 sp. off Spondylus ; L'pool Col. 



554. Leiosteaca likeaeis, n. s. 



L. t. minima, gracillimd, alba ; axi recta; apice acutd; 

 anfr. is., 2^)'ii^io declivioi'e ; nitente, vix vancosd ; aperturd 

 2)t/rifu)'mi, continud ; lahio rimulam umhilicalem formante ; 

 columella liaud callosd. 



Distinguished by its minute size, and extremely slender 

 growth. The habit is that of Leiostraca, though the varices 

 can scarcely be traced. Lonrj. "072, long. spir. '05, lat. "022, 

 div. 15". 

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



Tablet 2025 contains the specimen. 



555. Leiosteaca ? iota, var. betexta. 



Comp. Eulima iota, C. B. Ad. Pan. SMls, no. 290, pp. 198, 

 dl7.— Sow. Tlies. Conch, in loco.— JT. cj* A. Ad. Gen. i. 236. 



L. ?iota, axirectd. 



The form above indicated accords somewhat better with 

 the Panama species thau with the British, but is ' entirely 

 without twist. The British specimens are also sometimes 

 straight. The shells in this genus afford so very few distinctive 

 characters that no species can be certainly established without 

 an accurate knowledge of the animals. The onlj' two specimens 



