NAVICELLA. 



Species 19. (Fig. a, b, Mus. Cuming.) 

 N.ivicELLA Crepiduloides. Nav. testd suhatiguste ovatd, 

 de^n'essa, versus apicem attenuate rostratd, suhtus ex- 

 cavatd, caruleo-nigrd, olivaceo-luteo minute lineatd et 

 punctata, ared columellari latd, plano-decUvi, tenui, 

 semipellucidd. 

 The Cuepidula Navicella. Shell rather narrowly 

 ovate, depressed, attenuately beaked towards the 

 apex, e.\cavated beneath, blue-black, miuutely liue- 

 ated and dotted with olive-yellow, columellar area 

 broad, flatly slanting, thin, semitranspareut. 

 Hah. ? 



Of depressly excavated growth, peculiarly attenuated 

 and beaked towards the apex, the columellar area having 

 the appearance of a thin septum as in some species of 

 Crepidula. 



Species 20. (Fig. a, b, Mus. Cuming.) 

 Navicella eeticdlata. Nav. testd depresse ovatd, 

 teuiti, semipellucidd, liitescente, apicem versus roseo- 

 tinctd, olivaceo-niyro aperte reticiclatd, ared columel- 

 lari pared. 

 The reticulated Navicella. Shell depressly ovate, 

 thin, semitranspareut, yellowish, tinged with rose 

 towards the apex, openly reticulated with olive-black, 

 columellar area small. 

 Hob. Ceylon. 



A thin semitranspareut oblong-square ovate shell, reti- 

 culated W'ith a rather large open pattern. 



Species 21. (Fig. a, b, Mus. Cuming.) 

 Navicella insignis. Nav. testd subtrigono-ovatd, pecu- 

 liariter depressissime expansd, concentrice rude cor- 

 rugatd, apiee non inarginali, olivaceo-nigrd, versus 

 nMrginem lutesceute puuctatd, iutus carulesceute, ared 

 columellari parvd, contractd. 

 The remarkable Navicella. Shell somewhat trian- 

 gularly ovate, peculiarly very depressly expanded. 



concentrically rudely wrinkled, apex not marginal, 

 olive-black, dotted with yellow towards the margin, 

 interior bluish, columellar area small, contracted. 

 Hab. Sumatra ; Captain Martin. 



Eemarkably distinguished by its depressly expanded 

 Patella-V\k& form, the margin being produced much be- 

 apex. 



ad the 



Species 22. (Fig. a, b, Mus. Cuming.) 



Navicella apiata. Nav. testd ovato-trigond, utrinque 

 nlatd, de])ressissim.d, oUvaceo-nigro midi(/ue pulckerrimi 

 mimttimme retictilatd, iiitus cisrulesceute,maculis sub- 

 amplis duabus iiigris, ared columellari angustd. 



The finely-netted Navicella. Shell ovately trian- 

 gidar, winged on each side, very depressed, beauti- 

 fully finely netted throughout with olive-black, in- 

 terior bluish, with two rather large black spots, co- 

 lumellar area narrow. 



Le Guillou, Recluz, Eevue Zool. Soc. Cuvierienne, ISl-l, 

 p. 376. 



Hab. Nukuhiva, Feejee Islands. 



Conspicuously characterized by its depressed 

 expansion, and peculiarly neat minute reticulated marking. 



Species 23. (Fig. a, b, Mus. Cuming.) 



Navicella psittacea. Nav. testd anguste ovatd, versus 

 apicem atteuuate rostratd, valde gibbosd, atrd, obscure 

 reticulatd, iutus ceerulescente, ared columellari declivi, 

 margiiie medio coiispicue producto, superiie ru/o-tinctd. 

 The parrot-beak Navicella. Shell narrowly ovate, 

 attenuately beaked towards the apex, very gibbous, 

 black, obscurely reticulated, interior Ijluish, columel- 

 lar area slanting, margin conspicuously produced in 

 j the middle, tinged with red at the upper part. 



j Hab. Australian Islands. 



' A narrow gibbous shell, of light substance, attenuately 

 I beaked towards the apex, with the columellar area pro- 

 I duced in the middle into a tongue-like process. 



