AS NO DOUN, 
PLaTE XXIV. 
Species 92. (Mus. Sowerby.) 
Awnopon Bucuanensis. An. test@ subrhomboided, com- 
pressd, oblonga, olivaceo-fuscd, concentrice sub- 
rugata, intus salmoned ; latere postico oblongo, 
obscurissime biangulato ; margine dorsali recto ; 
margine terminali oblique truncato ; margine ven- 
trali medio subcontracto; latere antico brevi, 
rotundo. 
Bucuan’s Anopon. Shell subrhomboidal, compressed, 
oblong, olive-brown, concentrically _ slightly 
wrinkled, coloured within; posterior 
side oblong, very obscurely biangular, dorsal 
margin straight, terminal margin obliquely trun- 
cated; ventral margin slightly contracted in the 
middle ; anterior side short, round. 
Lea. Obs. on Unio, I1., p. 47, pl. 14, f 43. 
Hab. Buck Creek, Ohio. 
salmon 

, 
Species 93. (Mus. Sowerby.) 
An, testa subcylindraced, sub- 
radiata, 
ANODON CYLINDRACEA. 
compressa, fuscd, 
striis exilissimis concentricée rugatd, postice inflata, 
latere pos- 
obscurissime  viridi 
medio compressa, intts ceruled ; 
tico subexpanso ; margine dorsalis elevato ; mar- 
gine ventrali medio contracto ; latere antico angusto 
compresso, brevi, rotundo. 
CYLINDRICAL ANopoN. Shell subcylindrical, sub- 
compressed, brown, very obscurely rayed with 
green, wrinkled with very narrow concentric 
strie, posteriorly inflated, compressed in the 
centre, blue within; posterior side rather ex- 
panded, dorsal margin elevated; ventral margin 
contracted in the middle, anterior side narrow, 
THE 
compressed, short, round. 
Lea. Obs. on Unio, IL., p. 45, pl. 18, f. 40. 
Hab. River Medellin, near Vera Cruz. 
This species, from the contraction and depres- 
sion of the middle part, has a slightly reniform 
appearance. 
Species 94. (Mus. Sowerby.) 
ANODON PLANA. An. testd ovatd, magnd, tenui, inflata, 
concentriceé leviter rugatd, olivaceo-fuscd, ad latera 
nigrescenti, intus salmoned ; latere postico oblique 
producto, obscure 
cuneato ; 
biangulato ; margine dorsali 
laterali 
declivi, termino truncato ; margine ventrali postice 
inflato; latere 
margine ventrali sursdm acelivi. 
FLATTENED ANopoN. Shell ovate, large, thin, in- 
flated, concentrically lightly wrinkled, 
brown, blackish at the sides, 
within ; posterior side obliquely produced, ob- 
scurely biangular, dorsal margin straight, cuneate, 
recto, margine subexcavato, 
antico breviusculo, subrotundo ; 
THE 
olive- 
salmon-tinted 
lateral margin subexcavated, sloped, end truncated; 
anterior side rather short, a little rounded, 
ventral margin sloping upwards. 
Lea. Obs. on Unio, I., p. 160, pl. 7, f. 18. 
Hab. Bear’s Creek, near Louisville. 
It has a flatter dise than Anodon cataractus, and is 
much less transverse than that species. 

Species 95. (Fig. a, b, Mus. Sowerby.) 
ANODON AmMETHYsTUS. An. testd cylindrica, solidd, 
elongata, inflata, levigatd, castaned, ints pur- 
pureo-iridescenti ; latere postico producto, lined 
elevatd post angulum radiata, infra acuminatim 
productd ; margine dorsali subarcuato, postice de- 
clivi ; latere antico brevi obtuso. 
Tue ametuyst Anopon. Shell cylindrical, solid, elon- 
gated, inflated, smooth, chestnut, iridescent purple 
within; posterior side produced, rayed with an 
elevated line behind the angle, acuminately pro- 
duced beneath; dorsal margin slightly arched, 
posteriorly sloped downwards ; anterior side short, 
obtuse. 
Sowerby. 
Hab. ——? 
A very remarkable species for the evenness of its 
chestnut-brown epidermis and its brilliantly iridescent 

purple interior. 
August, 1869. 
