I A N T H I N A . 



Species 6. (Fig. 6 a and 6 d, Mus. Cuming.) 

 Ianthina fragilis. lanih. testa depresso-conoided, 

 anfractlbiu su/jplano-decliviius, striis obliquis minu- 

 tis et spiralibus impressis, undique decusiatu ; supra 

 violaceo-albicante, infra interne niolaced ; columella 

 ■mbrecld. 

 The fragile Ianthina. Shell depressly conoid, whorls 

 rather flatly sloping, everj'where decussated with mi- 

 nute oblique and spiral impressed strise ; violet-white 

 above, deep-violet beneath; columella nearly straight. 

 Lamarck, Syst. des Anim. sans vert. 1801, p. 89. 

 Ianthina striulata, Carpenter. 

 Eab. West Indies; Mazatlan ; California. 



Lamarck appears to have confounded two other species 

 with this, naming it first /. fragiUs and afterwards I. com- 

 munis. For the second of these from the Atlantic and Me/' 

 diterranean, the name /. communis should be retained. 

 For the third, inhabiting our own shores, I propose to 

 take the name /. Britannica, given to it, according to Mr. 

 Jeffrey, by Dr. Leach. 



Species 7. (Fig. 7 a and 7 b, Mus. Cuming.) 

 Ianthina c^ruleata. lantk. testa depresso-turblnatd, 

 spird parvd, anfractibus deelivi-convexis, oblique sub- 

 rude pUcato-striatis, spiraliter dense minute malleato- 

 striatis ; intense cceruleo-violacea, versus apicem albi- 

 cante, fascia lata pallida circa columellam ; columella 

 subrectd, appresso-reflexd ; aperturd transversa, medio 



The blue-stained Ianthina. Shell depressly turbi- 

 nated, spire small, wborls slopingly convex, obliquely 

 rather rudely plicately striated, spirally densely mi- 

 nutely indentedly striated; deep blue-violet, whitish 

 towards the apex, with a broad pale band round the 

 columella; columella nearly straight, appressly re- 

 flected ; aperture transverse, sinuated in the middle. 



Hab. ? 



The special sculpture of this species appears in the form 



of minute indented strise, and the colour is of a peculiar 



blue-staiued violet. 



Species 8. (Eig. 8 a and 8 b, Mus. Cuming.) 

 Ianthina Africana. lanth. testa subgloboso-turbinatd, 

 ventricosd, apice subobtusd, anfractibus deelivi-convexis, 

 deinde subangulatis, spiraliter superficialiter sulcaio- 

 siriatis ; supra carulescenle-albidd, infra purpuras- 

 cente-violaeed ; columella reflexd, a rcualu-productd, la- 

 bro subampliter sinuato. 

 The African Ianthina. Shell somewhat globosely 

 turbinated, ventricose, rather obtuse at the apex, 

 whorls slopingly convex, then slightly angled, spi- 



rally superficially groove-striated; bluish-white above 

 purplish-violet beneath ; columella reflected, arcuatcly 

 produced, lip rather largely sinuated. 

 Hab. Zanzibar. 



Belonging to the same typical form of the genus as 

 f. grandis, it is nevertheless more slopingly convex than 

 that species, and is distinguished by a strong peculiarity 

 of colouring. The delicate purplish-violet of the base 

 terminates suddenly at the angle of the whorl, so as to 

 show an unusually defined boundary. 



Species 9. (Fig. 9 a and 9 i, Mus. Cuming.) 



Ianthina planospirata. lantli. testa depressd, anfrac- 

 tibus deelivi-convexis, deinde subacute rotundatis, ob- 

 lique subrude plicato-striniiJi ; citrulescente-albd, ad 

 perip/ieriam purpuraseente-violaced ; columella arcu- 

 atd, subdilatato-refiexd ; aperturd transversd, medio 

 sinuatd. 



The FLAT-SPiHED Ianthina. Shell depressed, whorls 

 slopingly convex, then rather sharply rounded, ob- 

 liquely rather rudely plicately striated; bluish-white, 

 purple-violet at the periphery; columella arched, some- 

 what dilately reflected ; aperture transverse, sinuated 

 in the middle. 



Adams and Reeve, Moll. Voy. Samarang, p. 54. pi. 11. 

 f. 10. 



Hab. Atlantic Ocean. 



Taken in the Atlantic by Sir Edward Belcher. It is 

 less sharply angularly formed than I. fragilis, and is white- 

 banded round the columella. 



Species 10. (Fig. 10 a and 10 i, Mus. Cuming.) 

 Ianthina trochoidea. lanth. testd pyramidali-conicd, 

 solidiusculd, anfractibus deelivi-convexis, nUimo an- 

 gulato, ad basin plano-concavo, decussatim strialis, 

 suluris subrudibus; caruleo-albidd, basi purpuras- 

 eente-violaced; columella tenue refexd, subconlortd ; 

 aperturd ad angulum sinuatd. 

 The trochoid Ianthina. Shell pyramidally conic, 

 rather solid, whorls slopingly convex, last whorl 

 angled, flatly convex at the base, decussately striated, 

 sutures rather rude; bluish-white, purple-violet at the 

 base; columella thinly reflected, slightly twisted; 

 aperture sinuated at the angle. 



Hab. ? 



Of rather solid growth, distinguished from all the other 

 species of the genus by its regular trochoid form. The 

 boundary of the purple colouring is as sharply defined 

 round the basal angle as in the preceding species. 



December. 1858. 



