431 



tion of the tube in the adult Bhell of this and sonic Other specie 18 

 also well worth attention. 



Sect. C. Fartulcm. 

 Cceca leeviii : t. setpius utrinque contractu, qpertura declivi. 



In form and texture, some of the species approach the adult state 

 of Meioceras : others pass into the more typical groups. Tin v .in 

 named from their likeness in shape to a little sausage. 



26. Cecum l.eve, C. B. Ad. (diagn. auct.). 



C. {Fartulum) t. junior e " C. undatum " fere exacte simulante, 

 paulum graciliore; t. adulta eidem simili, sed Usvi, nitida, 

 subdiaphana, brunneo tincta; anticeet postice minus contracta; 

 aperturam versus inter dum tumente ; operculo concaro, suturis 



Mini's ilistiiictis. 



Test. jun. long. '035, lat. '005— 01. 

 Test, adult, long. -07, lat. -018. 



llab. Panama, 2 sp. (C. B. Ad.) ; Mazatlan, not uncommon. 

 Mob. Brit. 



C. B. Ad. Pan. Shells, pp. 162, 311 ; Maz. Cat. p. 325. 



So like is this shell, even in many minute particulars, to C. undo* 

 tuni, that a single specimen might have been taken for an extreme 

 variety of it. A careful examination of at least 200 specimens, 

 however, clearly proves their distinctness. 



27. Cecum bimargin'atum, n. s. 



C. (Fartulum) t. " C lseve "fere exacte simulante ; plants trim- 

 cationis ad unguium 100°; septo unyulato, apiee minus elevato, 

 Bubdextrorsum sito ; maryine laterali recto sen paulum con- 

 vexo : operculo multispirali, subplanato, bimaroinato. 



Long. -0/H, lat. -015— -022. 



Huh. Singapore, nestling in Lithophayus borrow in Plicatula ; 

 Australia, nestling in Petaloconchus nerinaoides. Bios. Brit. 



The fortunate discovery of a specimen with the operculum in situ, 

 presenting a double rim round the edge, as in some of the Cyclosto- 

 fmda, furnished a satisfactory character to distinguish the K. Indian 

 from the very similar Mazatlan species. The attempt t<. extract it 

 was, however, unsuccessful ; and the original specimen Iron; "Plicatula 

 perished after the description had been written. Five others from 

 the neighbouring seas, but without opercula, are provisionally allotted 



to the same species. (Sec howcxer note ' to SO. II. •nfrn.) 



Two young specimens of uncertain locality (from shell-washinj 

 init probably from the E. Indie-, an- doubtfully referred to t l»i-, 

 species on accounl of the similarity in the plug (Br. Mas 



I scum hiiiimiv, ( !pr. 

 ('. (Fartulum) t. "C. leevi" simili, sed albida, aperturm mum* 



