4 University of Michigan 
The bibliographic references are brought down to January 
I, 1922. 
FUSCONAIA EBENUS (Lea), 1831 
Type locality: Ohio River. 
Obovaria obovalis Rafinesque, ’20, p. 311. 
Umio ebenus Lea, ’31, p. 84, pl. 9, f. 14. 
Ouadrula ebena (lea) Simpson, 14, p. 897. 
Quadrula obovalis (Raf.) =Q. ebenus (Lea), Vanatta, ’15, p. 558 
(“type” examined). 
Although the so-called (Rafinesque-Poulson) “type” of O. 
obovalis Raf. has been identified as U. ebenus Lea, the orig- 
inal description of the former can be applied to several spe- 
cies (ebenus, subrotundus, and even to forms of the genus 
Pleurobema, U. plenus for instance). Nothing is said of the 
peculiar incurved beaks of ebenus and the deep beak cavities. 
Thus. obovalis cannot be recognized from the original descrip- 
tion, and ebenus Lea is valid. 
FUSCONAIA SUBROTUNDA (Lea), 1831 
Type locality: Ohio. 
Obliquaria sintoxia Rafinesque, ’20, p. 310. 
Unto subrotundus Lea, ’31, p. 117, pl. 18, f. 45. 
Obl. sintoxia Raf.= Obl. triangularis Raf., ’20, Conrad, 734, p. 72 
(the latter not identified; see also under Pleurobema pyramidatum). 
Quadrula subrotunda (Lea) Simpson, ’14, p. 892. 
QOuadrula sintoxia (Raf.) =Q. subrotunda (Lea), Vanatta, 15, p. 
558 (‘type” examined). 
Quadrula subrotunda (Lea) = Obl. sintoxia Raf., Walker, ’16¢, p. 
46, and ’18¢, p. 169 (“if identifiable”). 
Fusconaia subrotunda (lea) Ortmann, ’I9, p. 7. 
Vanatta says that Unio subrotundus Lea is preoccupied by 
Obliquaria subrotunda Raf. ’20; that this is not so has been 
pointed out by Walker (716°). 
Obl. sintoxia Raf. cannot be recognized, in fact, according 
to the measurements of the “type” given by Vanatta, it. 
