﻿I,AMPSILIS 149 



and two curved laterals ; right valve with one pseiidocardinal 

 and a vestige of another above it, with one lateral ; beak cavities 

 shallow, with a few rather large scars ; anterior cicatrices sep- 

 arate ; posterior cicatrices well impressed ; nacre bluish-white 

 to salmon, generally silvery iridescent and slightly thinner be- 

 hind. The male shell is full and sometimes a little angular on 

 the basal line just behind the center, and ends in a rounded or 

 slightly biangulate point behind, midway up from the base. 

 The female shell has a strongly developed, rather angular mar- 

 supial swelling at some distance from the posterior end ; from 

 the swelling to the elevated posterior point it is truncated. It 

 is smaller than the male shell. 



Length (male) 50, height 30, diam. 20 mm. , i 



Length (female) 40, height 28, diam. 20 mm. 



Texas, north to Kansas ; Missouri ; southern Illinois and In- 

 diana ; south through Tennessee, Alabama, Mississippi, and 

 Louisiana. 



Type locality. DeWitt Co.. Tex. 

 Unio parvus Conrad, Monog. II, 1836, p. 20. pi. ix, fig. i. — 



Hani.ey. Biv. Shells, 1843, p. 196, pi. xxii, fig. 3. — Sowerby, 



Conch. Icon., XVI, 1866, pi. xxxv, fig. 186. 

 Unio tcxasicnsis Lka, Pr. Ac. N. Sci. Phila., IX, 1857, p. 84. 

 Unio texascnsis Lea, Jl. Ac. N. Sci. Phila., IV, i860, p. 359, 



pi. i.xi, fig. 184: Obs., XVIII, i860, p. 41, pi. uxi, fig. 184. — 



CAI..1.. Pr. Ind. Acad. Sc, 1896, p. 3, pi. v, figs. 38-40. 

 Margaron (Unio) te.vaseiisis Lea, Syn.. 1870, p. 49. 

 L.ampsiiis texascnsis Simpson, Syn., 1900, p. 563. 

 Eitrynia fCaninculina) tcxa^ensis Ortmann, Ann. Car. Mus., 



VIII, 1912, p. 339. 

 Unio tcxasianus Sowerbv. Conch. Icon., X\^I, 1866, pi. XL, 



fig. 218. 

 Unio bairdianiis Lea. Pr. Ac. N. Sci. Phila., I, 1857, p. 102 ; Jl. 



Ac. N. Sci. Phila., IV, i860, p. 361, pi. lxi, fig. 186; Obs., 



VIII, i860, p. 43, pi. LXI, fig. 186. 

 Marvaron (Unio) hairdianus h^^, Syn., 1870, p. 49. 



