ASN Or! DTO EN. 
PLATE 
Species 84. (Mus. Sowerby.) 
ANODON EXILIS. An. testd tenu2, elongatissimd, angustd, 
valde inequilaterali, olivaceo-fuscd, nigro concen- 
trice teniatd, politd, intus pallide fulvd ; margine 
cardinali incrassato ; latere postico productissimo, 
oblique radiatim bianguloso, inter angulos ad ter- 
minum truncato ; latere antico brevissimo, rotundo, 
margine ventrali convexo, posticé magis inflato ; 
umbonibus obliquis, subprominentibus, acute tuber- 
culatis, 
narrow Awnopon. Shell thin, very elongate, 
narrow, very inequilateral, olive-brown, concen- 
trically narrow-banded with black, polished, inside 
pale fawn; cardinal margin thickened ; posterior 
side much produced, obliquely radiately biangu- 
lated, truncated between the angles at the end; 
anterior side very short, rounded, ventral margin 
THE 
convex, more inflated posteriorly; umboes ob- 
lique, rather prominent, sharply tuberculated. 
Lea. Obs. on Unio, II., p. 81, pl. 22, f. 68. 
Hab. ? 


Species 85. (Mus. Sowerby.) 
Awnopon ovata. An, testd ovatd, tenwi, inflata, politd, 
supra grisea, infra flavida, radiatim vivide viridi 
fasciata et strigatd ; concentricé lineata, posticé 
nigrescenti et biradiatd, intus alba ; latere postico 
arcuatim inflato, obscure biangulato ; margine 
dorsali rectiusculo, ad terminum cuneato ; margine 
laterali oblique convexo, ad terminum subacuminato ; 
margine ventrali convexo, medio subcontracto ; latere 
antico brevi, supra cuneato, concentricé subrugato. 
TuE ovate Anopon. Shell ovate, thin, inflated, polished, 
grey above, yellow beneath, rayed with bright green 
bands and stripes; concentrically lineated, poste- 
riorly blackish and biradiate, white within; poste- 
rior margin inflated in an arch, obscurely biangular, 
dorsal margin rather straight, cuneate at the end; 


XXII. 
lateral margin obliquely convex, subacuminate at 
the end; ventral margin convex, a little contracted 
in the middle; anterior side short, cuneate above, 
concentrically slightly wrinkled. 
Lea. Obs. on Unio, II., p. 2. 
An. var. Anodon opaca. Lea? 
Hab. Marietta, Ohio. 

Species 86. (Mus. Sowerby.) 
ANODON FLUVIATILIS. An. testd elongata, tenu2, inflata, 
concentrice  subrugatd, olivaceo- fusca, inths 
argenteo-alba ; latere postico radiatim inflato, 
obscure biangulato ; margine dorsali subelevato, 
subalato, cuneato; margine laterali excavato ; 
margine terminali inter angulos oblique truncato, 
ad terminum inferiorem acuminato ; margine ven- 
trali verstis terminum surstum acclivi, medio vix 
contracto; latere antico brevi, rotundato ; um- 
bonibus prominulis, ad apices acute tuberculatis. 
FLUVIATILE ANopoN. Shell elongated, thin, in- 
flated, concentrically rather wrinkled, olive-brown, 
silvery white within; posterior side radiately in- 
flated, obscurely biangulated, dorsal margin rather 
elevated, subalated, cuneate ; lateral margin ex- 
cavated, terminal margin obliquely truncated be- 
tween the angles, acuminated at the lower end ; 
THE 
ventral margin sloped up towards the end, very 
slightly contracted in the middle; anterior side 
short, rounded; umboes rather prominent, sharply 
tuberculated at the apices. 
Lea. Obs. on Unio. 
Anodon marginatus. 
Hab. Massachusetts. 
Say ? 
The umboes of this shell are not flattened and finely 
undulated as in An. Cygneus, but tumid and sharply 
tuberculated at the apices. 
August, 1869. 
