269 MAZATLAN TTNIVAtVES 



I 



Oedee PECTINIBHANCHIATA. 



S0EORDEE EOSTEIFEEA. 



Family VAjS'ICOEID.E. 



Genus VANICOEO, Quoj/ Sf Gaim. 



Vanikoro, Quoff ^ Gaim., Voy. a prima manu ; (postea Sigaretu3 

 sou Velutina,)— G^ra^/, Proc. Zool. Soc. 1847, p. 156, no. 256. — 

 E. S( A. Ad. Gen. vol. i. p. 374 



Narica, Red. in Sagr. Cub. Moll. 1836, teste PMl. Handh. 

 Conch, p. 184. — "M. Eecl. has the intention to form a genus," 

 D'Orb. Cuba, vol. ii. p. 39 : genus constituted, 1841: teste 

 Gray. 



Merria, Gray, Zool. Beech. Voy. 1839, p. 137, (anim. descr.) 



Leucotis, Siva ins. 1840, Treatise, p. 346. 



330. Vanicoeo cetptophila, n. s. 



V. t, parvd, Siffarefoided, ienui, albida ; nucleo anfr, iii. 

 quorum pritnus planatus, alteri suhtnrriti, ienuissime striati, 

 declivitcr sito ; anfr. normalibns ii. rapide augentibus,stibplana' 

 tis, irregulai-ifer striuUs spiralibus creberrimis et striis incre- 

 menti, interdum his, inferdum illis superantibus, ienuissime 

 cancellatis ; aperturd vaJde expansd, rix 2}eripheHar/i penul- 

 iimam. attingente ; labro elongato, labio recto ; umhilico maximo ; 

 peripherid angustiorc. 



This little creature resembles the Calyptroeida? in its seden- 

 trry habits, frequenting the burrows of worms, &c. in Spondylus 

 and Cbama valves, where its flattened form and advanced lip 

 (in this respect resembling Trochita) allow it to live in a very 

 narrow space. Many specimens were found in situ, but there 

 was no trace of operculum. A minute shell of one wliirl (found 

 inside the mouth of another,) is perfectly formed, like a tumid 

 Planorbis. Another, which was adhering over the umbUicus of 

 an adult, is just preparing to commence the normal portion, 

 3.nd is shaped like a IBithinia. It then lays its spire sideways, 

 but not always at the same angle, and begins a flattened 

 Sigaretoid growth. The sculpture is extremely variable, 

 sometimes nearly evanescent. Most of the 85 specimens found 

 were ver.v small; the nuclear shell measures '02 by '016; a 

 remarkably large specimen meas\ircs long. '15, lat. "17 by 15, 



