194 



Long. med. 4^ polL, lat. 6| polL; valvae periplicria 

 saepe 18 polL, et diam. (per nates) 3 polL 



Anodontarum maxima quas auctor vidit. 



Legit H. R. Schoolcraft in fluvio Missisippi superiori a 

 Prairie du Chien usque ad lacum Pepin. 



Schoolcraft, expedition through the upper Missisippi. 

 p. 154. 



2. Anodonta subvexa T, Jl, Conrad, 



An. testa subovali, inflata, tenui, anterius rotundata, 

 posterius subtrmicata; margine dorsali postice elevato, ab- 

 rupte rotundato; callo dentis rudimentum aemulante; nati- 

 bus medianis, prominentibus, inflatis, undulatis; epidermide 

 olivacea, obscure radiata; intus margaritaceo-caerulea, ce- 

 reo-maculata. — Th. M.- 



Long. supra 2 polL 



Regio umbonum inflata, angulata, pone eam radii. 



E collectione acad. sc. nat. Philadelph. — Hab. in 

 Black Warrior flumine. 



Silliman American journal. Vol. XXV. p. 341. et pl. L 

 fig. 12. 



3. Anodonta declivis T, Jl, Conrad, 



An. testa subovata, tenui, sub ventricosa , posterius pro- 

 ducta, truncato-cuneata; margine dorsali fere recto; nati- 

 bus prominulis, tuberculatis; regione umbonali angulata; 

 striis incrementi obscuris, rugosis; epidermide viridi-oliva- 

 cea, lineis longitudinalibus obscuris zonata; intus cerea, ad 

 marginem margaritacea, viridi-iridescente. — Th. 31. 



Long. 3~ poll. 



Pars posterior pone regionem umbonalem depressa. 



E collectione acad. sc. nat. Philadelph. — Hab. per- 

 rara in Flint flumine regionis Morgan in Alabama. 



Silliman American journal. Vol. XXV. p. 341. et pL L 

 fig. 11. 



4. Anodonta teres T. Jl, Conrad, 



An. testa anguste elliptica, inflata, postice producfa, 



