UNIO 533 
Unio michaudiana Des Mou ins, Actes Soc. Linn. Bord., VI, 
1833, p. 27, plate. 
Potamida sicula Swainson, Treatise on Mal., 1840, p. 282, 
fis: 58: 
Unio siculus HAN zy, Biv. Shells, 1856, p. 383, pl. xx, fig. 19. 
Unio arade Puiiarr1, Enum. Moll. Sic., Il], 1844, p. 49.— 
Kuster, Conch. Cab. Unio, 1854, p. 105, pl. xxvirt, fig. 6.— 
KoseE.t, Icon., IV, 1876, p. 62, pl. cxvu, figs. 1146, 1147. 
Unio dactylus MoreLet, Moll. Port., 1845, p. 110, pl. xiv, fig. 2. 
Kose rt, Icon., new ser., VI, 1893, p. 98, pl. cxxx, fig. 1132. 
Unio mucidus More.er, Moll. Port., 1845, p. 111.—KoBeE.r, 
Teon. new. ser, VL, 1893; p: 68, CLXXX, figs. 1130, 1131. 
Unio quinqueannulatus KustTER, Conch. Cab. Unio, 1854, p. 93, 
pl. xxv, figs: 3,4. 
Unio pallens Kuster, Conch. Cab. Unio, 1854, p. 95, pl. xxv, 
fie) 5X MVE, hie. Te ; 
Unio wiridiflavus Kuster, Conch. Cab. Unio, 1854, p. 96, pl- 
Rev, figs) 25°39: 
Unio petroviciti Kuster, Conch. Cab. Union, 1854, p. 98; pl. 
RVI, fig: 5; Xxvit, fig. 1. 
Unio maltzani Kuster, Conch. Cab. Unio, 1854, p. 106, pl. 
EXEN, MISS: f° 2: 
Unio baletonicus KustEer, Conch. Cab. Unio, 1861, p. 231, pl. 
RR RVILI STs 
Unio proechus Bourcutcnat, Rev. et Mag., XIV, 1862, p. 19, 
pl. x1x; figs: 1-3. 
Unio actephilus Bourcuicnat, Rev. et Mag., XIV, 1862, p. 20, 
Bi xixehose7, S: pl, xx, fig. 2. 
Unio lawleyanus GENTILUOMO, Bull. Mal. Ital., I, 1868, p. 54, 
pl. tv, figs. 1-3. 
A species having a wide distribution and one that is abun- 
dant, yet it does not seem to me to be especially variable or 
that there is the slightest necessity for the great number of 
names, which have been bestowed upon it. It is an elongated, 
rather cylindrical, bright colored and rather smooth form, us- 
