UNIO 559 
Unio (Rhombunio) halepensis Koper, Icon., new ed., XIX, 
1912, p. 20, pl. Dxx1I, figs. 2709-2711. 
Unio corbiculiformis Koseit, Icon., new ed., XIX, 1912, p. 
227 pi, DIT, 119, 27 12. 
Unio (Rhombunio) babensis Korey, Icon., new ed., XIX, 
{Ol2, cp. 22, ply DEXI, fie. 2713. 
Unio graeteri Kope.t, Icon., new ed., XIX, 1912, p. 23, pl. 
DXXII, fig. 2714. 
Unio (Khombunio) emesaensis Kovexr, Icon., new ed., XIX, 
1912, p. 24, pl. DxxI1I, figs. 2715, 2716. 
Unio (Rhombuno) rhomboidopsis \osELT, Icon., new ed., 
MOEX, 1012, p: 25,- pl. DxXxi, fig. 2717. 
Unio (Rhombunio) naegelet Koseir, Icon., new ed., XIX, 
TQM a ee255 ple DMT, 1S. 2718. 
Unio blanchianus Koper vt, Icon., new ed., XIX, 1912, p. 27, 
pl. Dxx1v, figs. 2719, 2720. 
Unio beroeus Kosei’, Icon., new ed., XIX, 1912, p. 29, pl. 
DXKIV, fies 2722. 
This form seems to replace U. littoralis in Asia Minor. It 
is generally smaller than that species, less rhomboid and more 
inflated. Some specimens are almost suborbicular, though 
they preserve the tendency towards being rhomboid; others 
are almost as rhomboid as littoralis, but are, as a rule, shorter. 
Locard’s figure of U. simonis in the Archives shows a slightly 
larger form than I have seen, and it is decidedly rhomboid. 
He may have known the reason for separating U. rhomboid- 
opsis from this species, but I do not. 
For this species, U. rothi Bgt., and U. homsensis Lea Ger- 
main, (Bull. Mus. Hist. Nat.. 1911, p. 67), has recently pro- 
posed a new subgenus, Rhombunio, but without specifying the 
characters upon which it is based. 
UNIO HOMSENSIS Lea. 
Shell long rhomboid, subcompressed, solid, inequilateral ; 
beaks somewhat elevated but not full, their sculpture not ob- 
served; posterior ridge full, widely rounded, ending behind 
near the base of the shell; dorsal line curved but ending in an 
angle behind at the oblique truncation of the posterior slope ; 
