﻿s p n j: E III M. 



Plate II. 



Species 11. (Mns. Brit.) 



SpH.ERIUM .NUn.KUS. <Sj.//. Irsf.t tin,n.hi,„n:t,i,nUlihi, 

 corned, fiiseiit; ijriseis orudfd, siihrhoiiihoidud; suh- 

 cequihUcndi ; umbonilms nuignis, obtiisis, margine 

 (lormli utriiique rectiusculo, margine ventrali rec- 

 tiiincuhi, iiuirghiibus lateraUhm subtruiicatis. 



The nut-like Sphj;ei0.\i. Shell tumid, high, pale, 

 horny, ornainented with grey band.s, subrhom- 

 boidal, nearly equilateral ; umboes large, obtuse ; 

 dorsal margin rather straight on each side, 

 ventral margin rather straight, lateral margins 

 a little truncated. 



Sti'der. Jay's Catalogue. 



J7,r/,. JMoravia. 



Species 12. (Mus. Brit.) 



Srnj,RlUM PISIDIOIDE. Cyr. testa viridi, subdistanler 

 sidmld, obliqiid, tiimidd, latiori quarn alia; latere 

 ^vjstico oblique producto, margine dorsali declivi ; 

 latere antico breinori, margine dorsali declivi; 

 nnibonilms elevaiis, tumidis, rotimdis. 



The pisidium-shaped Sph.ekium. Shell green, rather 

 distantly grooved, oblique, tumid, longer than 

 high ; posterior side obliquely produced, dorsal 

 margin sloped downwards, anterior side shorter, 

 dorsal margin sloped, umboes elevated, tumid, 

 ronnded. 



Gray. MS. Brit. Mus. 



ITab. Europe. 



Species 13. (Mus. Brit.) 

 Sphjirium striatlnum. Sjih. testa siihrhoin.boided,sub- 

 dlstanfer sukatd, obliqiid; latere antico brevi, liris 



ralid;s:h,l.r.'i.,..i;ru,>h!;.j„ii,rnd,n:f„.„dnHn-g!>,em 

 ventr.ih',.: .-',/»,.; ,,„,,»/,,/,-, //V/s ,v»/.,v„»/.//,-',- >,(.(/■- 

 ginedoisni; ,l,ri;n\ i.mr.juir j,.,.ll,;:-i'itrr'ili nhllqm 

 tniHCato. 

 The little striated Sph.erium. Shell rather rhom- 

 buidal, rather distantly sulcated, obli(ine; ante- 

 ri(ir side short, ridges strong; posterior side ob- 

 liquely produced, obtusely angular at the ventral 



margin, ridges almost disappearing ; dorsal 

 margin sloped, postero-Iateral margin obliquely 

 truncated. 



Lamarck. Anim. s. Vert. Cyclas, Sp. 10. 



Uah. South America. 



Species 14. (Mus. Brit.) 



SpH.EKHIM TrMlt-l'M. .S'y./*. IrMd sn!.,:./,nnll tuuiidd. 

 r„i:.li W ,i;s/„„!r,- i;r.,t.:,/Hs,:,..;.n,r.!.„lt.;.n,tn^ 

 s„h,n,n,„lH!: hihrr .uii;.;. r.dawln. Intrrr j.nsfin, 

 si,l,nbti,j,w prndnrin, i.,:q:c utargiumo r,:,d rakm 



snb,,. 



The tumid Sph.erid.m. Shell rather round, tumid, 

 strongly and distantly ridged, horny-brown, 

 high, rather orange within ; anterior side round, 

 posterior side rather obliquely produced, acumi- 

 nated near the posterior margin. 



Baird. Proc. Zool. Soc. 18G3. p. (39. 



Uah. Vancouver's Island. 



Species 15. (Fig. .', /-, PI. IV.) 



SpH.ERIUM PARTUMEIDM. Sjih. tr.</,! i:iillid,itJilvidd, Vfl 

 grU,,,.o,r„r.\ .<„I„:,tn,„l,i, lumidu. „lt,!. h,rigat,1 ; 

 l.il.rr „„ln;. l.r.ri. rutinnln; l„tr,;: i.nsliro s,,!,^,,;: 

 durln, ,in„i,„i,lrnl.. 



The pkoductive Srn.ERiCM. Shell pale yellowish, 

 horny-grey, rather rounded, tumid, high, smooth ; 

 anterior side short, round ; jwsterior side a 

 little produced, rather square. 



Say. Gould. Invertebi-ata, p. 75. f. 55. 



Unh. Ohio. 



Species 10. (Mus. Brit.) 



Sph.erium rugosum. S]}h. testa solid! iisculd, suhrhonu 

 boided, snhviridi-fiiscd, medio sidcald, ad laterii 

 Iwvigatd; latere anticn hm-i, ad inarginem dorsalein 

 svbcuneuto, latere truncal^ ; Inlrre yostico produclo, 

 oblique fruncato. 



The rugose SPHJ)RinM. Shell rather solid, sub- 

 rhomboidal, greenish-brown, sulcated in the 



