﻿TRUNCILLA 23 



TrUNCIIXA person ATA (Say). 



Shell solid, subtrian;?ular or subquadrate, inflated, inequilat- 

 eral, beaks full and high ; posterior ridge only moderately 

 developed; surface inegularly concentrically sculptured; epi- 

 dermis greenish-yellow, brownish or greenish-brown in old 

 shells, with faint wavy rays, often silky or cloth-like ; pseudo- 

 cardinals triangular, ragged, two in the left valve, one to 

 three in the right ; laterals short, usually double in each valve ; 

 muscle scars somewhat impressed; nacre white or flesh-col- 

 ored, thinner behind. Male shell f ubtriangular ; posterior 

 ridge usually feebly double ; in front of it is a wide radial de- 

 pression. Female shell usually subquadrate; marsupial swell- 

 ing occupying the place of the radial depression, slightly swol- 

 len, radially sculptured and toothed, thin and excavated within. 



Length (male) 57, height 48, diam. 33 mm. 



Length (male) 44, height 46, diam. 28 mm. 



Length (female) 54, height 43, diam. 33 mm. 



Length (female) 46, height 42, diam. 26 mm. 



Ohio River drainage. 



Type locality, Wabash River. 

 Unio personatns Say, New Harm. Diss. IL N©. 20, 1829, p. 



309.— Conrad, Monog., V, 1836, p. 47, pi. xxiv.— Kuster, 



Conch. Cab. Unio, 1852, p. 48, pi. x, fig. i.— Rf.eve, Conch. 



Icon., XVL 1864, pi. XV, fig. 64. 

 Margarita (Unio) personatns Lea, Syn., 1836, p. 33 ; 1838, p. 



23- 



Margaron (Unio) personatns Lea, Syn., 1852, p. 35 ; 1870, p. 



38- 

 Scalenaria personata Agassiz, Arch, fur Naturg.. L 1852, p. 



43- 

 Trunrilla personata Simpson, Syn., 1900, p. 522. 



Unio pileits Lea, Trans. Am. Phil. Soc, IV, 1834, p. 1 19. pi. 

 xvHi. fig. 47; Obs., I, 1834, p. 129, pi. xviii. fig. 47.— 

 Chenu, 111. Conch., 1858, pi. xv, figs. 2, 2a, 2&.— Reeve. 

 Conch. Icon., XVI, 1864, pi. xiv, fig. 59. 



Margarita (Unio) pileus Lea, Syn. 1836, p. 20; 1838, p. 17. 



Margaron (Unio) pileiis Lea, Syn. 1852, p. 24. 



