Occasional Papers of the Museum of Zoology 69 



tion, for every word of it applies as well to Plcnrobeina pyra- 

 midatum (Lea) : shell thick, swollen, ovate-triangular, the 

 three sides curved, a light oblique and longitudinal depression ; 

 epidermis nearly smooth, black ; nacre rose-purplish ; size 2-^ 

 inches. In fact, the black epidermis and the size fit U. pyra- 

 midatiis better than U. sulcatus. 



Thus the name obliquata cannot be revived. 



DvsNOMiA (PilEa) turgidula (Lea), 1858 

 Type locality: Cumberland River and Florence, Ala. 



Unio turgidulus Lea, '58, p. 40 (male). 



Utiio deznatus Reeve, '64, pi. 15, f. 61 (female). 



Truncilla deviata (Rve.) (male and female) Walker, 'lof', pp. 78, 81. 



Tr. florentina (Lea) (in part) and Tr. deviata (Reeve), Simpson. 

 '14, pp. 30-31. 



Tr. curtisi Frierson and Utterback, Utterback, '16, p. 190, pi. 6, f. 14, 

 pi. 28, f. 109. 



Tr. titrgidula (Lea) = U. deviatus Rve., Ortmann, '18, p. 590. 



Tr. curtisi Fr. and Ut t. = Tr. deviata (Rve.), Walker, 'i8<', p. 185. 



Walker Cio) was the first to indicate that turgidulus Lea 

 is the male of the female deviatus, by arranging his key for 

 the males of Truncilla in such a way that the characters seen 

 in turgidulus lead to the male of deviatus, but he did not 

 expressly stated this in the text, using only the name deviata, 

 while turgidulus has the priority. 



The identity of Tr. curtisi from the Ozarks has been recog- 

 nized by Walker ('18) and is evident from Utterback's 

 description and figures. The examination of authentic speci- 

 mens distributed by Utterback has settled this beyond any 

 doubt. 



DvsxoMiA (PilEa) torulosa (Rafinesque), 1820 



Type locality: Ohio and Kentucky River. 



Amblema torulosa Rafinesque, '20, p. 314, pi. 82, f. 11-12. 

 Amblcma gibbosa Rafinesque, '20, p. 315. 



