﻿lOO I.AMPSir.lS 



Unio >nississif>piensis Conrad, Jl. Ac. N. Sci. Phila., I, 1850, 



p. 277, pi. XXXVIII, fis'. II- — KusTER, Conch. Cab. Unio, 1861, 



p. 245, pi. Lxxxii, fi*;-. 3. — Reeve, Conch. Icon., XVI, 1865, 



pi. XIX, ^g. 85. 

 Margaron (Unio) mississip piensis Lea, Syn., 1852, p. 29; 1870, 



p. 60. 

 Unio riitersvillensis Lea, Pr. Ac. N. Sci. Phila., Ill, 1859, p. 



155 ; Jl. Ac. N. Sci. Phila., IV, i860, p. 355, pi. lx, fig. 181 ; 



Obs., VIII, i860, p. z'^, Pl- I'X. fig. 181. 

 Margaron (Unio) rutersznllensis Lea, Syn., 1870, p. 43. 

 Unio topeknensis Lea, Pr. Ac. N. Sci. Phila., XII, 1868. p. 144; 



Jl. Ac. N. Sci. Phila., VI, 1869, P- 313. pl- xlix, fig. 126; 



Obs , XII, 1869, p. 7:^, pi. xlix, fig. 126. 

 Margaron (Unio) topekaensis Lea, Syn., 1870, p. 43. 

 Unio cocodnensis Reeve, Conch. Icon., XVI, 1865, pi. xxiv, 



fig. 117. 



Var. fiirz'a n. v. 



Shell generally more attenuated than the type and less in- 

 flated, the marsupial swelling not so greatly developed. Epi- 

 dermis varying from pale or smoky-brown to chestnut, not 

 smooth or shining, occasionally with a few, faint posterior rays. 

 In a few cases this form has much the same size and shape of 

 typical specimens, but the color of the epidermis is always dark 

 and nearly ray less. 



Type locality. North Indiana ; Maumee River. 



An abundant species, especially in the southwest. Lea's Unio 

 nashviUianus appears to be a rather short, smooth, solid form. 

 The variety fiirva comes from northeastern Indiana and prob- 

 ably from the Maumee River drainage and seems to be almost 

 distinct enough to be worthy of specific raiik. Certain spec- 

 imens of it approach L. nasiita, but it is rather more inflated 

 than that species and the marsupial swelling is placed farther 

 back ; besides, it is diflferently colored. 



I^AMTSiMS LiENOSA (Conrad). 



Shell long elliptical or slightly olx:)vate, generally solid and 

 inflated, with a faint posterior ridge ; beaks moderate, the sculp- 



