﻿R T E L L A. 



Gci 



HOTELLA. 



Testa Irochifonnis, depresiia, orhiciilarls, solida, supcrne 

 conica, infra Icidiculan's, mtits nacrea; umhilico 

 per rtiUiim ohiocfo ; apertunt stvlilrujond, trans- 



'-'•-- '■/-'■'■"'" '•"'■"'", '>ndl!.p;r„lr i.h:n- 



,,rl,;r„I„,-r. 

 .Shell ti'ocliiform, depressed, orbicular, solid, conical 

 above, lenticular beneath, pearly within ; umlii- 

 licus covered in by a callus ; aperture rather 

 trigonal, transvers(>, operculum horny, plan- 

 orbicular. 

 Syn. Umbonium, Link. 



The few species to lie found towards the end of 

 this monograph which are placed in the IJritish 

 .Museum collection under the genoi-ic heading of 

 P! til 111 ill, do not so well agree with the above descrip- 

 tion as the more typical E. vestiitrin. Yet the pas- 

 sago is not very abrupt, and it seems hardly necessary 

 to keep up a distinction upon characters of so little 

 generic Lin])ortance. The species alluded to are 

 R. iiuanien.<is, and several others allied to it. The 

 East Indies appear to be the home of the B. vcstiaria, 

 although varieties of that species are quoted fi-om the 

 Mediten-anean. B. elcgans is from the Philippines, 

 and a variety from the Martinique. B. gifjantea 

 and other fine species are from Japan. 



Species 1. (:\[iis. Brit.) 



ROTELI.A CONHW. But. ifMd I'll^r,,-/:!! rjiil ninccnli, crassil, 

 rni,;.;ln,lh.niiir.ii;pnrr..,/n.r.,.f,i„n.s.i,.p;raUter 

 ii;.,...;!.,, iiir.i;.. ,/,^„v.s„, »///,.„ „„,>„./» cir.a 

 caUiiin centraleiii ijfpnvxo. 



The conical Rotella. Shell purplish-brown, thick, 

 conical ; ventral callus small, smoky-brown, 

 spirally deposited, depressed in the middle ; 

 last whorl depressed round the ventral callus. 



Aii.\5is & Reeve. Voy. Samarang. Proc. Zool. Soc. 

 lH.-,4. 



Eah. -i 



In this dark but richly-coloured shell the form of 



the callus is pecaliar, being formed of semicircular 



layers placed spirally. It is small, defined, and does 



not quite occupy the central hollow of the shell. 



Species '2. (Pig a, h. [,-, in Plate II.] Mus. Rrit.) 



ROTELL.4 HEI'NKssa. li'nl. iitriiiqiir l,',i I I'riihifi . ili'pnss,!: 

 anfrartilnix n:j,;.lr nr.<r, „i;t.iis. iiltinm ,„I ,„,ii:,i- 



ni'lll r„tirn,l,i, Sl,,„-riir i,lr,ln. I„lr fn^rinlo, filsri.r 



iiiiirijiii.e rcijulariter iinm-t.if,,, nl pi^riix ruilintix 

 riiri'eijato; callo expinmn, ijris,',.. Jnilirnhiri. 



The depressed Rotella. Shell lenticular on both 

 sides, depressed ; whorls rapidly increased, last 

 rounded at the margin, with a broad band in 

 the middle above, margin of band regularly 

 spotted, or variegated with rayed bands ; callus 

 expanded, grey, lenticular. 



A. Adams ? MS. Cum. Coll. 



Uah. ? 



Like Bdtella vestiarin, but with the last whorl 



moi'e spread. 



Species 3. (Fig. a, h, c, Mus. Rrit. and Sowerby. 



Rotella hio-inte. 



Bnf. I.'st/, 



conica, infra siihruuiplii iiat,h Mijn-:'i iii.'liiiiii tcnui- 

 ter spiraVitrr stri'il'i, ijrUni, iihimti.-: nnignis 

 ohUipus ni.r/resrriitil^ii.-^ n.l siitiii:,,,, rt u,J innjiilinii 

 ornata,aut grifr,; i',,i niurnlnl,: : inifnirtiljiis jirnjn 

 suturam (le2:)irgsis, siitnr,: juifinnlu .• nill,, In-cijii. 

 lari, rosea, post cohiiinihiin n iiijuhilini liiuiiiln: 

 columella crassissimd, Intil : hil'in rjtrriin siiperni- 

 producto et depresso. 



The gigantic Rotella. Shell rather high, conical 

 above, rather flattened below ; above the middle, 

 thinly spirally striated, grey, ornamented with 

 large obUque black spots at the suture and at 

 the angle, or grey without spots ; whorls near the 

 suture depressed, suture deep ; callus irregular, 

 pink, angularly tumid behind the columella ; 

 columella very thick, broad ; outer lip produced 

 and depressed above. 



Lesson. Illust Zool. PL 17. 



Mah. Japan. 



Species 4. (Pig. a, h, Mus. Brit.) 



Rotella costata. But. testa su2)erne conica, alti- 

 iiscula, infra plaiiiiisculd, avfractllms ad suturam 

 leviter elecatis turn, suhdepressis, sidcis spiralihus 



