AND EMBRYONIC FORMS. 435 



Unio ovattjs, Say. Nich. Bnoyc, Am. ed., Article Conch., pi. 2, fig. 7. 



Branchial uterus occupies the posterior part of the outer branchiae, rather small, 

 pendant, blackish on the inferior edges, having about twenty ovisacks, and is 

 altogether very like cariosus. Branchial very large, nearly semicircular, inner ones 

 much the larger, united the whole length of the abdominal sack. Palpi large, rather 

 thick, suboval, united one-third down the posterior edges. Mantle thin, with a very 

 broad margin, thicker on the edges, the female having a large fleshy process below the 

 branchial opening. Branchial opening rather small, with small papillae. Anal 

 opening small, slightly crenulate on the inner edges. Super-anal opening very large, 

 slightly united below. Color of the mass whitish. Adductor muscles very large. 



Embryonic shell pouch-shape, clear white, has no hooks. See Journ. Acad. Nat. 

 Sci. (2), vol. iv. pi. 5, fig.'15, and Obs. vol. vi. p. 47. 



Cincinnati, Ohio, J. Clark. White River, Indiana, D. H. Shaffer. 



Remarks. — Two females taken in White River early in November had the ovisacks 

 of the branchial uterus fully occupied with developed embryonic shells. 



Unio Blandingianus, Lea. Trans. Amer. Phil. Soc.,vol. v. pi. 15, fig. 44. Obs. vol. i. p. 213 



Branchial uterus occupies the whole width of the outer branchiaa. Branchial rather 

 large, inner ones much the larger, slightly curved below, free nearly the whole length 

 of the abdominal sack. Palpi thin, elliptical, united half down the posterior 

 edges. Mantle rather thick, dirty white, thicker and whiter on the margin and 

 particularly so at the branchial opening. Branchial opening large, dark brown on the 

 inner edges, with small papillag. Anal ^opening large, deep brown, with very minute 

 papillae. Super-anal opening rather large, united for a short distance below. Color 

 of the mass dirty white. 



Satilla River, Camden City, Georgia, Major T. C. Downie. 



Remarks. — While there were ova in the ovarium, as well as in the branchial uterus, 

 there were no embryonic shells perfected. 



Unio inflatus, Lea. = (Symj)hynota Injiata,) Lea. Trans. Amer. Phil. Soc, (2), vol. iv. pi. 14, fig. 28, 

 and Obs. vol. i. p. 109. 



Only two specimens were received, both being males. 



Branchial large, rounded below, inner ones somewhat the larger, united the whole 

 length of the abdominal sack. Palpi large, rounded below, nearly semicircular, united 

 one-third down the posterior edges. Mantle thin, with a wide margin, extending 

 into a large triangular flap to the wing. Branchial opening large, with numerous 

 small, brownish papillae on the inner edges. Anal opening small, with numerous 

 small papillae. Super-anal opening enormously large, united for some distance below. 

 Color of the mass whitish. 



Columbus, Mississippi, Dr. Spillman. ' 



