N I S C^ I A 



Genus Oxiscia, Soicerhij. 



Testa oblongo-ovata, basi emarginata, mb- 



hrevi, nunc acuminata, nunc depresM, aperturd elongatil, 

 angmtd, ttsque ad spiram extensd, labro columellari 

 latias/m' dilatato-reflem et (jranulato, labro externa 

 di'uticiihifo, iiwrassato, pleiiimgiie medio subcoarctato. 



Shell oblong-ovate, emarginated and a little recurved at 



spu'c 



sometimes acuminated, sometimes 



depressed, aperture elongated, narrow, extending as 

 far as the spire, columellar lip very broadly dilately 

 reflected and granulated, outer lip denticulated, 

 thickened, generally sUglitly contracted in the middle. 

 The genus Otdscia founded by Mr. Sowerby in his 

 • Genera of Shells' on the Linnaean Strombus oniscus {Cassi- 

 daria oniscus, Lamarck) has been universally adopted, as 

 representing a very characteristic and well-defined assem- 

 blage of characters. They were first remarked on the 

 appearance of the well-known Oniscia cancellata of the 

 China Seas, and their importance has been fully confirmed 

 by the discovery of several interesting new species. 



The OuiscifP are closely related to the Camidari/c, but 

 are uniformly of smaller size, of more solid growth, with 

 more elaborate sculpture, and remarkably distinguished by 

 a wide-spread dilation of the columellar. The outer lip is 

 also peculiar in being denticulated within. 



Of the localities known of tlie Oniscice three are from 

 the Western, two from the Eastern world. 



Species 1. (Mus. Cuming.) 



Onisci.\ oniscus. Oitisc. testa ollongo-ovatd, crassu, 

 apice mine oblusd, nunc mucronatd, costis fribiis vet 

 quatuor tuberculatis cinctd, tuberculis iiili-nlidit hipar- 

 titis, labro iucrassato, tumido, liris iii/rrriiptix in-niii- 

 laribits intus deutictdato ; albidd, niKvidix jH'rpmn'i'i 

 punctisqtte numerosis ca/'uleo-niffris aut fuscis aspersd, 

 labris interdum albis, interdum eximie rosaceis. 



The wood-louse Oniscia. Shell oblong-ovate, thick, 

 sometimes obtuse, sometimes pointed at the apex, 

 encircled with three or fom- tuberculated ribs, tu- 

 bercles sometimes divided into two, lip thickened, 

 swollen, denticulated within with irregular interrupted 

 ridges; whitish, sprinkled with a few spots and 

 numerous dots of brown or blue-black, lips sometimes 

 white, sometimes delicate pink. 



August, 



Sowerby, Genera of Shells, Oniscia, f. 4. 

 Strombus oniscus, Linnajus. 



Eadem var. Strombus Lamarckii, Deshayes. 

 Hub. Jamaica ; Gosse. 



The sli.ll s(l,M-ted for illustration is the pink-lip variety 

 to uliiili \L |i( -liayes has given the name 0. Lamarckii. 

 Till' wliiir \ariiiu's are usually of smaller dimensions, 

 but the characters are in aU respects the same. 



Species i. (Mus. Cuming.) 



Onisci.\ Strombiformis. Onisc. testa subtriyono-pyri- 

 formi, spird elevatd, apice mucronatd, anfractibus su- 

 perne angulatis, costis numerosis angustis nodosis cinctis, 

 labro columdlari hiinuli- ijraiuihito, labro e.derno tirato- 

 denticulato, lini lim-i inlcrriip/ii lnh-rreidente ; alba, 

 rufo-fusco miicnluld I'f piiiictiilii, hdiris albis. 



The stkombvs-shaped Oniscia. Shell somewhat tri- 

 angularly pear-shaped, spire elevated, pointed at the 

 apex, whorls angidated round the upper part, en- 

 circled with many narrow nodulous ridges, colu- 

 mellar lip minutely granidated, outer lip denticulated 

 with ridges, with a short interrupted ridge in the 

 interstices ; white, spotted and dotted with red brown, 

 lips white. 



Reeve, Pro. Zool. Soc, 1812. p. 91. Conch. Syst. vol. ii. 

 p. 310.pl. 353. f. 1. 



Hab. Honduras ; Dyson. 



Distinguished from the preceeding species by its sUghter 

 growth, more elevated spire, and finely nodided narrow 



Species 3. (Mus. Dennison.) 



OiNlsciA ExauisiTA. Onisc. testa subtrigono-ovatd, spird 

 brevi, acuta, anfractibus superne concavo-depressis, 

 tuberculis papiUaribus tmdique cingulatis, lira obseurd 

 intervenii'nte, labro columellari late expanse, granulis 

 valde irrcijiilarihiis, Inbro externo hicrassatim refkxo, 

 liris brcribns ilcntiformibus irregulariter mtmito ; 

 albidd, aiirautio-fusco hie illic sparsim punctata et pone 

 labrum trimaculatd, labris pallide purpureo-rosaceis, 

 apice rufo. 



The exquisite Oniscia. Shell somewhat triangularly 

 ovate, spire short, sharp, whorls concavely depresssed, 



18-19. 



