BIVALVE SHELLS. 281 



14. PisuM Canariense. 



p. testa ovali, compressiuscula, valde iiuequilaterali, subtiliter 

 striata, sordide albida, pellucida, umbonibus vix prominulis, 

 obtusis. 



Pisidium Canariense, Shuttleworth, Diagn.neuerMoll.no. I. \).\2. 



Hab. Teneriffa. 



15. PiSUM FERRUGINEUM. B.M. 



p. testa ovato-rbomboidea, subcompressa, tenui, cornea, ferri 

 oxydo ol)tecta, insequilaterali, transversim striata; extremitate 

 antica brevi, rotimdata, postica latiore, oblique subtruncata ; 

 apicibus acutis prominubs; dentibus lateralibus valvulcE dex- 

 tree prominentibus, antico acuto; superficie interna pallida 

 violaeeo-ferruginea. 



Pisidium ferrugineum, Krctuss,Sudafr.Moll.\).'] . no.2. pl.l. f. 7- 



Hab. Cajjut Bonse Spei in fluvio Knysua. 



3. America septentrionalis. 



16. PiSUM VIRGINICUM. 



P. testa minima, rotundata, subtiliter transversim striata, antice 

 rostrata (Gmelin). 



Pectunculus perpusillus, Lister, Conch, pi. 159. f. 15. 



Petiv. Gazoph. p. 1. pi. 104. f. 5 (mains). 

 Tellina virginica, Gmel. Syst. Nat. p. 32.36. no. 39. 

 Telliua pusilla (ex parte), Dillw. Cat. i. 106. no. "J^. 

 Cyclas virginica, Ferussac, Observ. Mag. de Zool. 



Hab. Respublica Virginia;, Americse septentrionalis. 



17. PiSUM MINUS. 



P. testa minima, ovata, insequilaterali, natibus tiimidis, approxi- 

 matis ; marginibus rotundatis ; dentibus omnibus crassis. 



Cyclas minor, Adams 8f Migh. Boston Journ. of Nat. Hist. 1842, 

 'p. 33. pi. 4. f. 2. 



Migh. Cat. of the Shells of Maine, Bost. Journ. of Nat. Hist. 

 iv. 319. 



Hab. In aquis dulcibus circa Stonington, Respublicfe Unitae 

 AmericcC septentrionalis. 



18. PiSUM ABRUPTUM. 



p. testa o\ata, valde insequilaterali, olivacea vel pallide castanea ; 



