430 UNIONID2E, THEIR SOFT TARTS 



laro-e colored on the edges and united for some distance below. Color of the mass 

 whitish. 



Cincinnati, Ohio, J. Clark. 



Unio zigzag, Lea. Trans. Amer. Phil. Soc, (2), vol. iii. pi. 12 fig. 19. Obs. vol. i. p. 54. 



Only two specimens were received, both males. Branchice small, inner ones much 

 the smaller, nearly semi-circular, free only at the posterior end of the abdominal sack. 

 Palpi small, thin, oval, united only at the upper part on the posterior edges. Mantle 

 very thin, thickened along the margin. Branchial opening rather large, with numer- 

 ous brownish papillae. Anal opening rather small, with numerous small brownish 

 papilke. Super-anal opening rather large, colored on the edges and united below. 

 Color of the mass whitish. 

 Cincinnati, Ohio, J. Clark. 



Unio Coopeeianus, Lea. Trans. Amer. Phil. Soc, (2), vol. v. pi. 8, fig. 21. Obs. vol. i. p. 173 



Branchial uterus - . No ova were found here, but they were in the ovarium. 



Branchice large, nearly semi-circular, free two-thirds the length of the abdominal sack. 

 Palpi rather small, elliptical, attached for a short distance down the posterior edges. 

 Mantle thin, with a wide and thickened margin. Branchial opening very large, with nu- 

 merous small papillae. Anal opening large, with numerous small papillae. ' Super-anal 

 opening rather large, united below. Color of the mass yellowish white. 



Cincinnati, Ohio, J. Clark. 



Unio metaneveus, Raf. An. des Sci. Phys. vol. v. p. 305. 



Branchial uterus . No ova were found here, but ova were in the ovarium. 



Branchice rather large, inner ones much the larger, curved posteriorly, but nearly 

 straight on the lower edges, free more than half the length of the abdominal sack. 

 Palpi large, thin, subtriangular, rather transverse, united for a short distance on the 

 posterior edges. Branchial opening very large, with numerous small brownish pa- 

 pillse. Anal opening very small, with no apparent papillae. Super-anal opening very 

 long, with well marked deep brown edges, united slightly below. Color of the mass 

 yellowish. 



Cincinnati, Ohio, J. Clark. Columbus, Mississippi, Dr. Spillman. 



Remarks. — This is another of the TJniones which are without papillae on the edges 

 of the super-anal opening. In about a dozen specimens examined, I found that the 

 females had the umbonial slope more raised than in the female. One of the dozen 

 had the super-anal opening not united below. 



Unio oebictjlatus, Hild. Am. Jouvn. Sci. vol. 14. 



Both specimens received were males. Branchice very large, very much rounded 



