70 L'niirrsily of Micliigav 



Uiiio f'crplcxus Lea. '31, p. 112, pi. 27, f. 42. 



U. torulosus Raf. = V. gibbosus Raf. = U. pcrplcxus Lea, Conrad, 



■34, P 72. 



U. gibbosus Raf. = ('. pcrplcxus Lea, Ferussac, '35, p. 27. 



L''. gibbosus Raf. = f/. torulosus Raf. ^ [/. perplexus Lea, Conrad, 

 ■36, p. 50, pi. 27, f. I. 



Truncilla pcrplcxa (Lea), Simpson, '14, p. 24. 



Tr. torulosa (Rai.) =^ Ambl. gibbosa Raf. := Tr. perplexa (Lea), 

 Vanatta, '15, p. 550 ("type" examined). 



Tr. torulosa (Raf.), Ortmann, '18, p. 589. 



Tr. perplexa (Lea)=^. torulosa Raf. = --:/. gibbosa Raf., Walker, 

 '18'^, p. 186 ("if identifiable"). 



"Lea's Unio perplexus is preoccupied by Say for a variety 

 of U. ridibiindiis not noticed by Simpson (Am. Con., Pt. I, 

 Binney's Reprint, p. 155)." (H. A. P.) 



Rafinesque's crude figure of A. torulosa is sufficient to rec- 

 ognize in it the female of this species, since it distinctly shows 

 the posterior expansion of the female shell and the character- 

 istic nodes. Also the description confirms the identity. A. 

 gibbosa undoubtedly is the male belonging here, and the two 

 large, nodulous ribs and the oblique furrow between them arc 

 unmistakable. This identification with perplexus Lea is sup- 

 ported by Vanatta's examination of the so-called Rafinesque- 

 Poulson "type." 



Conrad's first selection ("34) of the name torulosa in pref- 

 erence to gibbosa must stand, although he subsequently ('36) 

 reversed this. 



DvSNOMiA (D^SNoMiA) FLExuosA ( Rafiucsque ) . 1820 

 Type loeality: Kentucky, Salt, and Green rivers. 



Obliquaria flexuosa Rafincsque, '20, j). 3o5. 



Unio foliatus Hildreth. "28, p. 284, p. 16. 



Unio {Hpioblasma) biloba Rafinesque, '31, p. 2. 



U. gibbosus Raf. probably = Hpioblasma biloba Raf., Ferussac, '35, 

 p. 27-34 (authentic specimen of biloba examined). 



U. flcxuosus Raf. = foliatus Hild., Conrad, "35, p. 8, pi. 4, f. 2 ("type" 

 examined). 



