CHIEFLY OF THE UNITED STATES. 327 



had ova in the ovarium, nor embryonic shells in the branchial uterus. BrancMce 

 very large and rounded below, inner one being the larger ; united the whole length 

 of abdominal sack. Palpi large, elliptical, open on posterior side to the top. Mantle 

 very large, thin, with a broad thickened border. Branchial opening rather large, 

 with rather large coarse papillae. Anal openiTig large, with numerous very minute 

 colored papillee on the inner edges. Super-anal opening rather small, colored on the 

 edges and united below. Color of the mass whitish. All the specimens, old and 

 young, had pearly granulations on the middle of the cavity of the valves. 



Unio granulatus, Lea. Coosa River, Alabama, Dr. Showalter. — Six specimens were 

 received. None had charged branchial uteri, but ova were found in the ovarium. 

 BrancJiicB small, rounded below, the outer one shorter and extending, posteriorly, 

 beyond the inner one, free nearly the whole length of abdominal sack. Palpi very 

 small, very thin and subelliptical. Mantle very thin. Branchial opening small, with 

 a few papillag, terminating with a caruncle as in parvus, Bar. The four males have no 

 caruncle. Anal opening rather large and apparently without papillae. Seems to have 

 no super-anal opening. Color of the mass white. 



Unio consanguineus, Lea. Coosa River, Alabama, Dr. Showalter. — Four females 

 and one male. None had charged branchial uteri, but ova were found in the ova- 

 rium. Branchioi rather small, inner one much the larger and rounded. Free nearly 

 the whole length of abdominal sack. Palpi very small, thin and subtriangular. 

 Mantle very thin, dark along the edges. Branchial opening rather large, with papillae . 

 on the inner edges. Anal opening rather large, with very minute papillse. Supjer-anal 

 opening long, and colored on the edges. Color of the mass whitish. 



TInio Lewisii, Lea. Coosa River, Alabama, Dr. Showalter. — None of the specimens 

 received had ova in the ovarium, nor embryonic shells in the branchial uterus. 

 Branchiae large and rounded below, inner one much the larger, free nearly the whole 

 length of abdominal sack. Palpi very small, subtriangular, united above. Mantle 

 large, thin, thicker and colored on the margin. Branchial opening large, with 

 numerous papillae on the inner edges, which are dark. Anal opening small, with very 

 minute papillae on the inner edges. Super-anal opening long, and slightly colored 

 on the edges. Color of the mass whitish. 



Margaritana Holstonia, Lea. Coosa River, Alabama, Dr. Showalter. — Two speci- 

 mens only, both females, were received. One had ova in the ovarium, but there 

 were no embryos in the branchial uterus. The other had the branchial uteri filled 

 with embryonic shells matured in the branchial uteri. These were in form closely 

 allied to those of Anodonta undulata, Say. Branchial uteri extend the whole width of 

 the branchiae. Branchiw large, inner one the larger, free the whole length of 



