﻿LAMPSILIS 155 



pressed pseudocardinals and two straight laterals; right valve 

 with one pseudocardinal and sometimes a feeble tooth above it, 

 with one lateral ; beak cavities shallow but compressed ; muscle 

 scars shallow ; nacre bluish or purplish-white, richly iridescent 

 behind, scarcely thicker in front. The male and female shells 

 differ but little, the former is sometimes a little rhomboid, the 

 rounded posterior point being nearest the base ; the female shell 

 has a feeble, but long, marsupial swelling, and the posterior 

 point is about midway up. 



Ivcngth 38, height 22, diam. 15 mm. 



Type locality, Coosa River. Also Big Prairie Creek, Ala- 

 bama. 



Unio germanus Lea, Pr. Ac. N. Sci. Phila., V, 1861, p. 40; Jl. 

 Ac. N. Sci. Phila., VI, 1866, p. 49, pi. xix, fig. 54; Obs., XI, 

 1867, p. 53, pi. XIX, fig. 54. 

 Margaron (Unio) germanus Lea, Syn., 1870, p. 49. 

 Lampsilis germanus Simpson, Syn., 1900, p. 565. 

 Unio granulans Lea, Pr. Ac. N. Sci. Phila., V, 1861, p. 60. 

 Unio grannlatus Lea, Jl. Ac. N. Sci. Phila., VI, 1866, p. 48, pi. 



XVI, fig. 46; Obs., XI, 1867, p. 52, pi. XVI, fig. 46. 

 Margaron (Unio) grannlatus Lea, Syn., 1870, p. 49. 



This species has no strong characters, but it is less solid and 

 inflated than L. corvnnculus and /-,. cylindrella, and it differs 

 from the latter in the color of the nacre. It is darker colored 

 and much more sulcate than L. cromiwllii. 



Lampsilis cyeindrella (Lea). 



Shell long elliptical, with the dorsal and ventral lines nearly 

 parallel, solid, subinflated, with rather full, but not high, beaks, 

 their sculpture not seen ; posterior ridge low or wanting ; sur- 

 face tawny, rayless, with a thick epidermis ; left valve with two 

 stumpy pseudocardinals and two laterals ; right valve with one 

 pseudocardinal, and one lateral, which sometimes has a slight 

 ridge at its inner base ; beak cavities shallow, with one or two 

 pits ; muscle scars well impressed ; nacre whitish at the border, 

 rich coppery within, thinner and iridescent behind. The female 



