48 IOWA ACADEMY OF SCIENCES. 



Unio corvinus Lea. 



(Read June 2. 1868.) 



"Observations on the Genus Lhiio, Vol. XII, p. 70, PI. 

 XLVIII, Fig. 123. 



Unio corvunculus Ijea. 



(Read June 2. icSnS.) 



'•Observations on the Genus Unio, \o\. XII, p. 74, PI. L, 

 Fi.o-. 12 7. 



Unio vesicularis Lea. 



(Read Septemb?r 15, 1873.) 



"Observations on the Genus Unio" VoL XIII, p. 41, PL 

 XII, Fig. 34. 



The synonymy of this gronp, therefore, will stand as in 

 the sul)jolned lists and even here there is some doubt that the 

 Texas forms should be held to be distinct. 



Unio parvus Barnes. 



U. pca/Ius Lea. 

 U. minor Lea. 

 U. marginis Lea. 

 U. corvinus Lea. 

 U. vesicularis Lea. 



Unio texasensis Lea. 



U. hairdianus Lea. 

 U. hecdii Lea. 



Unio glans Lea. 



U. pullus Conrad. 

 CT. gramdatus Lea. 

 U. germanus Lea. 

 U. cromivelh'i he'A. 

 U. cT/IindreJlushen. 

 U. cormmcuivs Lea. 



Tlie xyi'O of the group is the form described b}^ Dr. Biirnes 

 to whicli Ixjth in anatomv, hai its and general characters all 



