162 C. A. Westerlund, Synopsis Molliiscorum Extramarinor. Scanclin. 



riores partes altitudine subsequalis, marginibus parallelis, 

 fuscopicea, rufescens, forte eeneo splendida, nnmquam ra- 

 diata, ad umbones ventricosa, infra et praecipue rostro 

 longo mediano, utrinque angustato apice subtruncato* forte 

 compressa; pars antica perbrevis, humilis, postica plus 

 quam quadruple longior, margine ventrali postice ascen- 

 dente; umbones lati, humiles, decorticati; ligamentum vali- 

 dum; dens card, crassus, elongatus, fere longitudinalis, 

 crenatus, lamellae crassse. Long. 110 (ant. 20, post. 85), 

 alt. 42, cr. 30 mm. 



Hah. Siiecia in Ostergotland (in lacubus Follingarne *, Ki- 

 sasjon et Kilarpsjon). Forma aegre interpretenda, ad iumidum 



vergens. 



^'^) C postice cUlatata et superne ])lus minus angidata, fu- 



scovirescens, scepe pidchre saturatius viride radiata et 

 fuscozonata, crassiuscula, umbones scepissime integri, 



dens card, parvus, compressus, obliquus. 



U. batavus Mat. & Rack. (Trans Soc. Linn. 1807). C. oblongo- 

 ovalis, postice dilatata, sat ventrosa, inferne et postice 

 compressa, antice rotundata, postice 272 longior, in ro- 

 strum latum, lingua?forme, fere medianum, subtruncatum 

 producta, margine dorsali arcuatulo, ventrali subrecto; um- 

 bones prominuli, ventrosi; ligamentum angustum, longum. 

 Long. 60—70, alt. 30 — 35, cr. 20 — 25 mm. — Rossm. Icon, 

 f. 128 a. 



Hab. Suecia in Skane (Hojea, Kopingea, Almaa &c.), Oster- 

 gotland (in Stangan) et Dalarne (in lacu Hyen, par. Schildvie). 

 — Dania in Sjaelland (Ringstedaa &c.) et Jylland. 



Forma minor (long. 40 — 50, alt. 25 — 28 mm.), obscurior, 

 subolivacea, zonis multis atrobrunneis, postice latior, subrhom- 

 bea, margine dorsali magis curvato, basali subretuso, in Hojea 

 et in Skenan occurrit. 



j-f Umhones tuberculato-rugosi, postice margine areali infe- 

 riori {callo obtuso) obliquo utrinque ab area distincti. Dens- 

 cardinalis valvce dextrce compressus, sat crassus, longitudi- 

 nalis, posteriorc valvce sinistrce valido. 



U. tumidus Retz. (Nov. test. gen. 1788). C. ovato-conica, ven- 



