SPARTZBRANCHIA. 205 
CYCLOSTOMA ELEGANS. 
C. testa ovato-conica. Anfractibus ventricosis, longitudinaliter 
et transversim elevato-striatis, rete efformantibus, striis trans- 
versis, minoribus sculptis. 
Turbo elegans, Lister, Conch. xxvii. f. 25; Anim. dang. t. i. 
f. 5; Act. Ang. 105. f. 2; Mont. Test. Brit. 342.—Supp. 
t. xxl. f. 7; M. & R. Trans. Linn. Soc. vii. 167 ; Flem. 
Edinb. Encyel. vii. 72; Dill. Dese. Cat. 781 ; Turt. Conch. 
Dict. 206. 
Nerita elegans, Miill. Verm. 181. no. 368. 
Turbo tumidus, Penn. Brit. Zool. 128. t. Ixxxii. f. 110. 
Turbo striatus, Da Costa, Brit. Conch. 86. t. v. f. 9. 
Cyclostoma elegans, Lam. Hist. Nat. des Anim. sans Vert. vi. 
148. 
Animal cinereum, lateribus subverrucosis, ceeruleo-nigrican- 
tibus. Tentacula griseo-cinerea, apice subpellucida. Oculi 
atri. Dorsum transyersim annulatum. 
Habitat in cretaceis et sabulosis vulgaris. Alt. 2 unc. 
Shell conically oval. Whorls ventricose, longitudinally and 
transversely striated with elevated lines, forming a net, the 
transverse strize smallest. Height five-eighths of an inch. . 
Animal ash-colour, with the sides subverrucose, blue-black. 
Tentacles greyish ash-colour, somewhat pellucid at their apices. 
Eyes black. Back annulated transversely. 
Inhabits chalky and sandy situations. 
ORDER VI. SPARTA BRANCHIA. 
Valvata et Paludina 4uctorum. 
Branchie fasciculis filamentorum ad cayitatem branchialem 
adheerentibus. Corpus conicum. Testa conica. Os rostri- 
forme, mandibulis duabus instructum. Tentacula duo, ad 
basin externé dilatata, oculigera. Sewus distinctus, ovo-vivi- 
parus. 
The branchiz are composed of bundles of filaments adhering 
