UXIO— Plate L.WVl. 



names liail previously been attaelied to otlier speeies, it 

 has been necessary to change the spceilic appellation. By 

 a typo°;raplucal error in Lea's Synopsis, tlic Uiiiopsis 

 Myliloiden was referred to the Unio so named by lla- 

 linesqne. 



species . 



(Mus. Hanlev.) 



I Mo ELONOATLS. Uii. tesid maf/nS, oblong'i, soliflii, coii- 

 r.cxd, nigro-piced, concolore, sublavigald, plicis incre- 

 menti tanlum corrugatd, ntr'mqne rolitmlald, aiitici 

 aitenuatd ; margine ■oeiilridi in medio vix subreiuso, 

 oniice nrcuatim, acclivi ; lunula, costnque iiinbonari. 

 nullis, iimionibus vix emiiientibus, natlbus nciitis, iu- 

 fexis; margaritd albido-lividd, maculis olimcinsfucu- 

 Id; denlibus laieralibus nullis. 



The long Unio. Shell large, oblong, solid, convex, of 

 an uniform pitcliy black, smooth, except for the pli- 

 ciform wrinkles of increase, rounded at each end, 

 tapering in front ; ventral margin scarcely at all in- 

 dented in the middle, arching upwards in front ; 

 neither a luuule nor an umbonal ridge, nmboes 

 scarcely projecting ; beaks acute, inflected ; nacre 

 livid white, v;ith stains of olive-colour ; no lateral 

 teeth. 



Lamarck, Anim. sans Vert., vol. vi. pt. 1. p. 70. 



Hab. Euroi)e. 



ight 



Speeies 399. (Mus. Hanlcy.) 



Unio UNDULATUS. Un. tedd ovatd, suba-qiiilnU-rali, va- 

 I liJfi, iiilidisaijiid, ventricosd, saturate olivaced, obscure 



xKhnidialii, hrxigaid, (ul uniboncs, uutem, pUcis panci-f, 

 perhKiguis renwlis, poslice dilatatis et arcuatim. devli- 

 ribus, subtramversim undatd ; margine ventrali arcu- 

 alo ; umbonibiis satis eminentibus, natibus ipsis parvis 

 infiexis ; lunula parvd, lanceolatd ; margaritd albd, 

 deidihus cardinatibus nullis. 



The waved Unio. Shell ovate, subequilateral, strong, 

 very glossy, ventricose, dark olive, indistinctly sub- 

 radiated, smooth, but waved at the umboes by a few 

 very large distant somewhat transverse folds, which 

 on the hinder side become dilated, and arch down- 

 wards ; ventral edge arcuated ; umboes moderately 

 elevated, the beaks themselves small and inflected ; 

 lunide small, lanceolate; nacre white, no lateral teeth. 



Say, Nichols. Encyc. (ed. Americ), vol. iv. pi. 3. f. 3. 

 Alasmodonta .iculptilis (young), Say. 

 Mga undulata. Wood. 

 Unio Mans, Valenc. (teste Lea). 

 Unio glabrata, Sowerby (teste Lea). 



Hab. Massachusetts, etc., North America. 



Alii, 



rgurilift'riis, lint not 



ed ventrallv. 



Species 398. (Mus. Haidey.) 



Unio Holstonianus. Un. testd parvd, subtenni, nitidd, 

 convexn, subovali, olivaced, concolore, lavigntd ; war- 

 gine ventrali in medio vix subreluso ; lunula, costdqne 

 nmbonali nullis, umbonibus huud eminentibtis, marga- 

 ritd albido-carulescente, nitidissimd ; r./argine cardi- 

 7iali angustd ; dentibus lateralibns nullis. 



Holston river Unio. Shell small, rather thin, glossy, 

 convex, suboval, of an olive-colour, not variegated, 

 smooth ; ventral margin scarcely in the least in- 

 dented ; neither a lunule nor an umbonal ridge ; um- 

 boes not projecting; nacre bluish-white, brilliant; 

 liinge-margin narrow ; no lateral teeth. 



Lea, {Margaritana), Trans. Amer. Ph. Soc, second ser. 

 vol. vi. (and Obs. Unio, vol, ii.) pi. 13. f. 1:5. 



Ilab. Holston river, U. S. North America. 



There are nsuallv some orange stains uikiii the nacre 



Species 400. (Mus. Hanlev.) 

 Unio Sikkimensis. Un. testd parvd, satis talidd, sub- 

 ventricosd, oblii/ue ohovatd, luted, concolore, subheri- 

 gatd ; margine rfnlnili arciinto, niriiiqiit' (rt antice 

 prffserti,i/J iicr/iri ; casta nuihunidi nulla ; uiargaritd 

 albidd, maculis licidis fncati! ; '.larg'iiic rarJiiiali lata, 

 valde arcuato ; dentibus cardinatibus calldis, laciniatis, 

 hand laminatis. 

 The Sikkiji Unio. Shell small, rather strong, subven- 

 tricose, obliquely obovate, of an uniform dirty yellow, 

 not sculptured ; ventral margin arched, rising more 

 l)articulnrly in front, no umbonal ridge ; nacre whit- 

 ish with livid stains ; liinge-margin broad, much 

 arcuated, cardinal teeth strong, jagged, not Lnmellar. 

 Lea, Obs. on Unio, vol. vii. p. 09. pi. 39. f. 131. 

 Ilab. Sikkim, East Lulies. 



The aspect of this insignificant-looking Unio, whose 

 eroded umboes preclude a more extended description, is 

 rather that of a native of North America than of Coiiti- 



