8 University of Michigan 
Unio multiplicatus Lea, ’31, p. 70, pl. 4, f. 2. 
U. heros Say = U. multiplicatus Lea, Conrad, ’34, p. 60. 
Quadrula heros (Say), Simpson, ’14, p. 825. 
Megalonaias heros (Say), Utterback, ’16, p. 43. 
Unio undulatus Bar. = U. peruviana Lam. (19) = U. giganteus Bar. 
=U. heros Say, Frierson, ’16¢, p. 63. 
U. undulatus Bar.=U. heros Say, Ortmann, 18, p. 539. 
“The original figures of Unio undulatus Barnes agree closely 
with some broad examples compared by Pilsbry (also by 
Frierson). In Barnes’ figure the characteristic tuberculation 
of heros would fall within the eroded area, the sculpture of 
which was but slightly indicated by the engraver; but the 
express statement of Barnes, ‘Disks tuberculated below the 
beaks,’ cannot be ignored. The figures might represent either 
heros or undulatus of authors (costatus Raf.), but the descrip- 
tion is certainly decisive for heros. 
“Unio giganteus was included by Barnes in U. crassus, 
which he described as waved. The only waved Unio seven 
inches long occurring in the region of Prairie du Chien is U. 
heros. 
“Probably the beak region was eroded and the tubercula- 
tion thus escaped notice. In the absence of any other species 
which fills the requirements, I believe with Frierson that 
Megalonaias gigantea should replace M. heros.” (H. A. P.) 
The view of Frierson that U. peruvianus Lam. is “almost 
certainly” this species cannot be maintained. The figure in 
the Encyclopédie cited by Lamarck is unmistakable. It has 
swollen beaks, which are not in evidence in gigantea, and no 
other points in the description indicate this species. In fact, 
peruvianus is the species generally known as U. plicatus Say. 
See Amblema peruviana, 
