Call — The Unionidce of Arkansas. 59 



Margaritana confragosa Say. 



New Harmony Disseminator of Useful Knowledge, 



Vol. II, No. 22, 1829, p. 339; American Conchology, 



Plate XXI, 1830. Described from the Wabash river, 



Indiana. 



Unio confragosus Say. So Reeve, Conchologia Iconica , 



Vol. XVI, Unio Plate LX, Fig. 299. A fine figure of 



the external view of the shell. 

 This species has occurred only in the St. Francis river, so 

 far as present information extends. It is a form which loves 

 to dwell in the soft mud of sluggishly flowing streams. Just 

 over the Louisiana boundary line, in Claiborne Parish, this 

 shell occurs in numbers. It is not without reason, therefore, 

 that it may be expected to occur in other portions of the State 

 of Arkansas than the one listed. 



Margaritana rugosa Barnes. 



Alasmodonta rugosa Barnes. Am. Jour, of Sci. and 

 Arts, 1st series. Vol. VI, 1823, p. 278, Pi. XIII, Figs. 

 21a, 21b; DeKay Natural History of New York, Vol. V, 

 Mollusca, p. 196, PI. XIV, Fig. 226. 1843. 



Unio rugosus Barnes. So Reeve, Conchologia Iconica, 



Vol. XVI, Unio Plate LX, Fig. 302, 1867. Reeve says 



this is equivalent to Unio ahducta Say, a species which 



we have been unable to find that Say ever characterized. 



Specimens were obtained in the White river, Carroll county ; 



and in the Saline, at Benton, where the form appears to be 



abundant. This shell has a wide range from New England, 



to west central Kansas, Texas, Louisiana, Alabama, and 



Georgia ; the northernmost range, that is authoritatively 



known, is the Rideau and Ottawa rivers, Canada. 



Anodonta edentula Say. 



Alasmodonta edentula Say. New Harmony Dissemin- 

 tor of Useful Knowledge, Vol. II, No. 22, 1829, p. 

 340 ; described from the Wabash river. 



Anodonta edentula Say. DeKay Nat. Hist. N. Y., Pt. 

 V, 1843, p. 201, Pi. XVI, Fig. 231; Lea, Trans. Am. 

 Philos. Soc, Vol. IV, 1858, p. 50, PL VI, Fig. 37. 



