FRESH WATER AND LAND SHELLS. 33 
which enlarges the posterior basal margin; cardinal teeth very large, thick, spread out, 
and deeply striate; lateral teeth short, thick, straight, with a large, flat plate separating 
them from the cardinal teeth; anterior cicatrices distinct and deeply impressed; posterior 
cicatrices confluent; dorsal cicatrices placed on the inner side of the plate; palleal cicatrix 
impressed; cavity of the shell rather deep and small; cavity of the beaks very deep and 
angular; nacre silvery white and iridescent. 
Remarks.—A single valve only was in the collection of Dr. Budd, and he thinks it came 
from the west of Georgia. I have had it in my possession for several years, and deferred 
describing it in the hope of getting more specimens; but in comparing it with its allied 
species, metanever, Raf., tuberosus, (Nobis,) and sparsis, (Nobis,) I have found it too dif- 
ferent in outline and some other characters to place it with either. It is much more 
enlarged on the posterior slope, which is almost winged, and it is without a groove on 
that part, which the other three have. In this specimen the groove over the middle of the 
valve is deeper than in the other species. The anterior portion is more enlarged than in 
the others, and it has many rather low tubercles, the general character of which, over the 
whole disk, is rather depressed and smooth. In the tuberosus and metanever the tubercles 
are generally more raised and roughened. The tubercles on the posterior slope in this 
specimen arrange themselves in curved rows, which, running to the margin, make it 
crenulate. 
The lateral teeth are remarkably short, straight, and very thick. The intervening 
plate between the cardinal and lateral teeth is exceedingly large and very flat. 
I dedicate this species to the memory of Rumphius, the author of “ D’Amboinsche 
Rariteitkamer.” 
Unio sacirrirormis. Pl. XXII. Fig. 35. 
Testa levi, valde transversd, compressa, ad latere planulatd, valde inequilaterali, posticé acute angulata ; 
nalvulis subtenuibus ; natibus parvis, prominulis, ad apices undulatis ; epidermide virido-fuscd, radiata ; den- 
tibus cardinalibus parvis, compressis, crenulatis ; lateralibus prelongis subrectisque; margarita purpured et 
zridescente. 
Shell smooth, very wide, compressed, flattened at the side, very inequilateral, acutely angular behind; valves 
rather thin; beaks small, slightly prominent, undulated at the tip; epidermis greenish-brown, rayed; cardinal 
teeth small, compressed, crenulate; lateral teeth very long and nearly straight; nacre purple and iridescent. 
Hab. Oconee river, near Athens, Georgia, Major Le Conte. 
My cabinet and cabinet of Major Le Conte. 
Diam. .6, Length 1.2, Breadth 2.7 inches, 
Shell smooth, very wide, compressed, flattened at the side, very inequilateral, acutely 
angular behind; substance of the shell thin; beaks small, slightly prominent, undulated at 
the tip and placed towards the anterior margin; ligament long and thin; epidermis brown- 
ish, with numerous broad, dark-green rays, covering the whole disk, with rather distant 
lines of growth; posterior slope somewhat compressed, with a single raised line passing 
from the beak to the posterior margin; umbonial slope rather acutely angular; cardinal 
teeth rather small, compressed, crenulate, double in both valves ; lateral teeth long, nearly 
2 
