THE FAMILY NAIADES. 



17 



W 



^; 

 o 



•-H 



H 



Eh 

 O 



i 



;5 



o 



OBLIQUE. 



-^sopus. Green. 



Unio cicatricosus. Co7i. ; not of ifoy. 

 Unio varicosus. Con. ; not of Lea. 



varicosus. Lea. 



Unio cicatricosus? Say.* 



perplexus. Lea. 



Unio. gibbosus ? jffo/! 

 Unio gibbosus. Con. 



WIDE. 



Leaii. Gray. 



granosus. Brug. Lam. 



tuberculatus. Bar. Eat. Hild. 



Novas Hollandiae. Gray. 



cylindricus. Say. Eat. Hild, 



Unio naviformis. Lam. Blain. Valen. 





spii 



Lea. 



* Never having seen the specimen described by Mr. Say as cicatricosus, 

 I am unable to decide if it be the same with varicosus, (nobis.) Two things 

 mentioned by Mr. Say induce me to doubt it. He calls his " a common spe- 

 cies," and says it is " distinguishable by the single series of transverse eleva- 

 tions on the middle." The latter remark does not apply to varicosus, and I 

 have always deemed it a rare shell. 



