296 Mr Jenyns's Monograph on the 



Cyclas cornea, Lamarck, 5. 558. — Pfeiffer, 120. t. 5. / 1, 2. — Nilsson, 

 Hist. Mollusc. Suec. QG.—Turt. Conch. Brit. 248. t. 11./ 14,.— Turf. 

 Man. 13./ 2. — Fleming, 452. 



Tellina cornea, Linn. Si/st. Nat. 1. 1120.— Gmel. 3241. — Linn. Trans. 

 8. 59.—Dillw. Cat. of Shells, 1. 104.— Don. Brit. Shells, t. 96- 



Tellina rivalis, Mull. Verm. Hist. 2. 202. 

 Cardium corneum, Mont. Test. Brit. 86. 



Cyclas rivalis, Draparn. 129. t. 10. / 4, 5.—B,arel, 222. /. 8. / 4, 5. 

 Far. /3. 



Testa subglobosa, versus marginem basalem complanata; umbonibus 

 tumidis, pellucidis, valde prominentibus. 



Long. 5^ lin. alt. 4|. Crass. 3^ lin. 

 Cyclas stagnicola, Leach 3ISS. Brit. Mus. 

 Tellina stagnicola, Sheppard, Linn. Trans. 14. 150. 



Animal album, viviparum: tubi siphonales subelongati, cameo pallide 

 colorati; superiore subconico, apertura parva apice perforato; infe- 

 riore cylindraceo, truncato, apertura ampliori : pes testam longitudine 

 paulb superans. 



Testa globosa, suborbicularis, ventricosa, tenuis, levissime striata; nunc 

 virescenti-fusca, zonis 1 — 3 lutescentibus, quarum 1 plerumque mar- 

 ginalis latior; nunc omnin6 fuscescens aut lutescens: umbones obtusi; 

 in var. /3 valde prominuli, quasi inflati, pellucidi : lunula vix ulla : 

 margo dorsalis postice litura nigricanti duplici sa^pe notatus : liga- 

 nientum cardinale inconspicuum. 



This very common species is a general inhabitant of rivers, ponds, 

 and ditches throughout the country, and appears to thrive equally well 

 both in running and in stagnant water. In confinement it will oc- 



