30 University of Michigan 
out entirely as insufficiently defined, there seems little reason 
for reconsidering Lea’s restriction, which has been accepted 
for three-fourths. of a century.%. (a ARP.) 
ELLIPTIO DILATATUS (Rafinesque), 1820 
Type locality: Ohio River. 
Unio dilatata Rafinesque, ’20, p. 297. 
Unio gibbosus Barnes, ’23, p. 262, pl. 11, f. 12. 
U. dilatatus Raf. =U. gibbosus Bar., Conrad, ’34, p. 68; Ferussac, 
g55(p. 275 Conrag,, 30..p.) 42,. pl. 21: 
Unio gibbosus Bar,, Simpson, ’14, p. 597. 
U. dilatata Raf.= Obliquaria sinuata Raf. =U. gibbosus Bar., Van- 
atta, “15, p. 555 (‘“‘types” examined). 
U. dilatata Raf.=U. gibbosus Bar., Walker, ’16¢, p. 46 and 18°, 
p. 175 (‘if identifiable”). 
Elliptio dilatatus (Raf.), Utterback, ’16, p 90; Ortmann, ’18, p. 556. 
The original description of dilatata Raf. indicates a long, 
elliptical, posteriorly somewhat attenuated, brownish shell, 
with violet nacre. This can be only one species of the Ohio, 
the gibbosus Bar., and the latter name has to give way to 
dilatatus. 
ELLIPTIO COMPLANATUS (Dillwyn), 1817 
Type locality: Maryland and New Jersey. 
For this well-known species Haas (Vid. Middel, Dansk 
Naturh. Foren., LXV, 1913, p. 54) has revived the name of 
Unio violaceus Spengler (1793), relying on the identification 
of the type. However, Walker (’18", p. 3) has shown that 
this name cannot be used, since the original description of 
violaceus is entirely insufficient to recognize the species. “More- 
over, the species had been named Mya complanata in the Port- 
land Catalogue, 1786, p. 100.” (H.A. P.) 
ELLIprio pRopuctus (Conrad), 1836 
Type locality: Savannah River, Augusta, Ga. 
Obliquaria cuprea Rafinesque, ’20, p. 304, pl. 81, f. 8-9. 
