﻿56 i.MvirsHjS 



of a third bcliind. and one truncated lateral ; beak cavities mod- 

 erate : muscle scars shallow, smooth ; nacre bluish. The female 

 shell has often a decided marsupial swellinj^:. 



Lenp^th (male) 70, hei0it 45, diam. 25 mm. 



Length (male) yy, height 50, diam. 32 mm. 



Length (female) 60, height 45, diam. 25 mm. 



Entire Ohio River drainage : Southern Michigan ; New 

 York? (Marshall). 



Type locality, Ohio. 

 Vnio multiradiatus Lea. Tr. Am. Phil Soc. TIT, 1829. p. 434, 



pi. IX, fig. 15; Obs., I, 1834, p. 48, pi. IX, fig. 15. — TiANLEY, 



Biv. Shells, 1843, p. 190, pi. xxi, fig. 10. — Ciienu, 111. Conch., 



1858, pi. XII, figs. 2, 2a, 2b. — SowF.Riiv, Conch. Icon., XVI, 



1868, pi. Lxx, fig. 506a. 

 Marg^arita flJnio) nmltirndiatits Lea, Syn., 1836, p. 24; 1838. 



p. 19. 

 Mar gar on (Utiio) multiradiatus Lea, Syn., 1852, p. 31 ; 1870, 



p. 42. 

 Lampsilis mnltiradiatiis Simpson, Syn., 1900, p. 532. 

 Unio fnsciolns Say, Am. Conch,, VI, 1834. — Conrad, Mon- 



ography, III, 1836, p. 26, pi. XI, fig. 2. — Kuster. Conch. 



Cab. Unio, 1852, p. 32, pi. v, fig. 4. 

 Unio perradiatus Lea, Pr. Ac. N. Sci. Phila., II, 1858, p. 40; 



Jl. Ac. N. Sci. Phila., V, 1862, p. 66, pi. vi, fig. 215; Obs., 



VIII, 1862, p. 70. pi. VI, fig. 215. 

 Margaron (Unio) perradiatus Lea, Syn., 1870, p. 37. 

 Unio aJtilis Reeve, Conch. Icon., X\'T, 1865, pi. xxiii, fig. 109. 

 Unio pcrovalis Sowerby, Conch. Icon., XVI, 1866, pi. xxxviii, 



fig. 209. 



This species is not very' closely related to any other form. 

 Its best distinguishing character is the numerous rays which 

 cover the entire shell except the beaks, which are often brown- 

 ish in well-preserved specimens. 



Lampsius doeiaris (Lea). 



Shell irregularly elliptical, inflated, subsolid, with moder- 

 ately full, high beaks and a decidedly developed, rounded pos- 

 terior ridge, which is sometimes faintly double and ends in a 



