SIGAEETUS.— Plate I. 



The concave Sigaretus. Shell globosely eav-sliaped, 

 obtusely conical, spire but little exsurted, whorls 

 slopingly veutricose, spirally flatly ridged, ridges 

 broad, interstices narrow, incised, more or less co- 

 vered with an epidermis ; ash-brou'n, spire livid- 

 violet, shining reddish-chestnut in the interior. 



Lamarck, Anim. sans vert. vol. i 

 Sigaretus ilraiji, Deshayes. 

 Sigaretus cijmbu, jMenke. 

 Sigaretus mnjcimus, Philippi. 



Ilab. Bay of Callao, Peru (on 



10. 



saud-biuik, and at a 



depth of ilve fathoms) ; Cuming. 



I do not participate in the opinion of M. Recluz and 

 M. Deshayes that this well-known species, (he largest of 

 the genus, was incorrectly figured by Jlr. Sowerby in his 

 ' Genera of Shells ' as Lamarck's S. cuiicriv/is. It is the 

 only species of the genus inhabiting the locality to which 

 Lamarck assigns it. 



Species 4. (Fig. o, b, Mus. Cuming.) 

 Sigaretus haliotoideus. Sig. testa oblique subglobosa, 

 spirn obtuse couicd, moilice exsertd, anfractihus declivi- 

 ventricosis, circa spiram depressiusculis, spiraliter 

 lineari-Uratis, epideniiide t'/uni indutis; aordidi fasces- 

 cenie. 

 Till'. Haliotis-like Sigaretus. Shell obliquely sub- 

 globose, spire obtusely conical, moderately exserted, 

 whorls slopingly ventricose, rather depressed around 

 the spire, spirally linearly ridged, covered with a 

 tiiin epidermis ; dull-brown. 



Helix liallotoidea, Linnieus, Syst. Nat. 10th edit. p. 775. 



Le Sigaret, Adanson. 



nulla velulina, Miiller. 



Sigaretus haliotoideus, Lamarck. 

 Hah. Mouth of the Gambia, West Africa. 



Here again the habitat assists in confirming the cor- 

 rectness of Mr. Sowerby "s views in figuring this species 

 in his ' Genera of Shells ' as the Liimaean Helix Jialiotoi- 

 deus, Le Sigaret, from Senegal, of Adanson. It is the 

 only West African species of the genus. It is less glo- 

 bose than the preceding species, with the spire more ob- 

 tuselv conical. 



Species 5. (Fig. a, b, Mus. Cuming.) 



Sigaketus Nekitoideus. Sig. testa obloiiyo-aurifornii, 

 solidiusculd, spird subterminaU, parvd, anfractu ulti- 

 mo depresse vei/tricoso, spiraliter lirnto-striato, coucen- 

 trice coustricte plicate ; albidd, epidermide lutescente 

 iudutd. 



The Nerite-like Sigaretus. Shell oblong ear-shaped, 

 i-ather solid, spire nearly terminal, small, last whorl 

 depressly ventricose, spirally ridge-striated, concen- 

 ti'ically constrictedly plicated ; white, covered with a 

 yellowish epidermis. 



Helix Neritoidea, Linnaeus, Syst. Nat. 12lh edit. p. 1250. 



Hab. Straits of Malacca. 



Of a much less globose form than either of the last two 

 species, generally rather constricted in growth. 



