418 UNIONIDiE, THEIR SOFT PARTS 



with numerous small, blackish papillae. Anal opening large, with numerous small, 

 black papillae. Super-anal opening large, black on the edge and united below. 

 Color of the mass dirty white. 



Embryonic shell short pouch-shape, white, has no hooks, very nearly of the same 

 form asjihaseolus. See Journ. Acad. Nat. Sci., vol. iv. pi. 5, fig. 12. Obs. vol. vi. p. 47. 



Columbus, Mississippi, Dr. Spillman ; Fox River, Illinois, H. C. Grosvenor. 



Remarks. — The female described above was from Dr. Spillman. Others exa- 

 mined were from Mr. Grosvenor and were smaller. Two of these were females hav- 

 ing ova in the ovarium. I was surprised to find these of an elliptical form, quite 

 different from the ordinary globular form. 



Unio exiguus, Lea. Trans. Auoer. Phil. Soc, (2,) vol. viii. pi. 7, fig. 1. Obs. vol. iii. p. 29. 



Only a single specimen, a male, was examined. 



Branchial very large, much rounded below, the inner ones the larger, united the 

 whole length of abdominal sack. Palpi large, subtriangular, thick, united for a 

 short distance on the posterior edges. Mantle thin, double and thick on the lower 

 margin, which is dark and maculate, and has papillae along the edges. Branchial 

 opening large, with numerous reddish-brown and black, rather coarse papillae. Anal 

 opening large, very dark reddish-brown, with small papillae on the edges. Super-anal 

 opening very large, dark-brown and maculate on the inner edges, united below. 

 Color of the mass whitish. 



Roswell, Cobb County, Georgia, N. A. Pratt, Jr. 



Unio striatus, Lea. Trans. Amer. Phil. Soc, (2,) vol. viii. pi. 12, fig. 16. Obs. iii. p. 41. 



Branchial uterus . No ova were found, but they were in quantity in the 



ovarium. Branchial large, nearly semicircular, inner ones much the larger, free 

 nearly the whole length of abdominal sack. Palpi small, subelliptical, united only 

 at the upper part of the posterior edges. Mantle thin. Branchial opening rather small, 

 with very small papillae. Anal opening large, with numerous very small papillae. 

 Super-anal opening large, united below. Color of the mass whitish or light-salmon. 



Roswell, Cobb County, Georgia, N. A. Pratt, Jr. ; and Baldwin County, Georgia, 

 J. Postell. 



Unio oCcidens, Lea. Trans. Amer. Phil. Soc, (2,) vol. iii. pi. 10, fig. 1(5. Obs. vol. i. p. 49. 



Branchial uterus occupies about one-third of the posterior portion of the outer 

 branchiae, being in long ovisacks, which are extended below the line of the branchiae 

 and are blackish on the lower margin. Branchial large, semicircular, inner one the 

 larger, united the whole length of abdominal sack. Palpi rather large, thin, suban- 

 gular, united nearly half way down the posterior edges. Mantle rather thin, with 



