452 UNIONIDiE, THEIR SOFT PARTS 



ened at tlie basal margin. Branchial opening small, blackish, with numerous small, 

 flesh-colored papillae. Anal opening small, reddish-brown, without papillae. Super- 

 anal opening very small, united for some distance below. Color of the mass whitisb. 



Embryonic shell triangular, brown, with hooks, very like Anodonta Lewisii. See 

 Journ. Acad. Nat. Sci., (2), vol. iv. pi. 5, fig. 32. Obs. vol. vi. p. 49. 



Near Darien, Georgia, J. Hamilton Couper, Esq., and Major T. C. Downie. 



Anodonta plana, Lea. Trans. Amer. Phil. Soc, (2), vol. vii. pi. 7, fig. 18. Obs. vol. i. p. 160. 



Branchial uterus occupies the whole length of the outer branchiae. Branchiae very 

 large, rounded below, inner ones somewhat the larger, thickened along the edges, free 

 half the length of the abdominal sack. Palpi very large, subtriangular, united half 

 way down the posterior edges. Mantle thick, much thickened at the margin, black 

 on the outer posterior basal portion of the edges, and brownish along the fringes. 

 Branchial opening large, with numerous rather large papillae. Anal opening rather 

 large, without papillae on the edges. Super-anal opening large, blackish on the edges, 

 united for some distance below. Color of the mass light salmon, more intense on 



the foot. 



Embryonic shell triangular, brown, has hooks, nearly the same with ovata. See 

 Journ. Acad. Nat. Sci., (2), vol. iv. pi. 5, fig. 33 and Obs. vol. vi. p. 49. 



Columbus, Ohio, H. Moores. 



Anodonta decora, Lea. Trans. Amer. Phil. Soc, (2), vol. vi. pi. 20, fig. 63. Obs. vol. ii. p. 64. 



Branchial uterus occupies the whole length of the outer branchiae, the young giving 

 the whole mass a brown color. Branchim very large, rounded below, inner ones 

 rather the larger, free two-thirds the length of the abdominal sack. Palpi rather 

 large, very thin, rather oblique, subfalcate, united one-third way down the posterior 

 edges. Mantle very thin, much thickened on the margin. Branchial opening rather 

 large, with numerous, delicate, light-brown papillae, somewhat branched. Anal 

 opening small, without papillae. Super-anal opening small, colored on the edges, 

 united for some distance below. Color of the mass salmon. 



Embryonic shell subtriangular, brown, has hooks. See Journ. Acad. Nat. Sci., (2,) 

 vol. iv. pi. 5, fig. 34, and Obs.vol. vi. p. 49. 



Columbus, Ohio, H. Moores ; and Cincinnati, D. H. Shaffer. 



Anodonta ovata, Lea. Trans. Amer. Phil. Soc. (2), vol. x. pi. 2, fig. 2. Obs. vol. ii. p. 2. 



Branchial uterus occupies the whole length of the outer branchiae, which are enor- 

 mously extended, the young giving the whole mass a brown color. Branchial very 

 large, much rounded below, inner ones rather the larger, free more than half the 

 length of the abdominal sack. Palpi very large, rather thin, subtriangular, darker 



