Occasional Papers of the Museum of Zoology 55 



Toxolosina Uz'idum (Raf.) = {7. glans Lea, Frierson, '14*, p. 7. 



Toxolasma lividum (Raf.) =(7. pullus (Con.) (part) = t/. mocstus 

 Lea =: U. cylindrelius Lea, Ortmann, '18, p. 573. 



U. (Tox.) lividus Raf. = Car. glans (Lea) or possibly = />jJ/!(J 

 Con., Walker, 'iS''. p. 180-181 ("if identifiable"). 



This is the form representing Car. glans Lea in the tipper 

 Tennessee region, but it dilTers from the typical glans of the 

 interior basin at least as a variety. 



It has been claimed by Frierson and Ortmann that U . Hindus 

 Raf. is this form. It is, according to description, a small 

 shell (i inch) of elliptical shape, "swelled,"' not thick, with 

 rough, brown epidermis and livid purple nacre, from Rock 

 Castle River, Kentucky ( Upper Cumberland ) . ' ! ! i 



This description ma} be applied to two species of this region, 

 the present one and Ligumni ivnu.veincnsis (Lea), and there 

 is nothing in it which permits a final decision. Moreover, the 

 dimensions given by Rafinesque fit in part (diameter 37% of 

 length) both species, in part (height 75%) neither of them. 

 Thus lividus is not recognizable and cannot be used, and with 

 it the generic name Toxolasma must be rejected. Occasional 

 specimens of zwnt.vonoisis have cjuite exactly the proportions 

 given by Rafinesque. 



U. pullus Conrad resembles this form very much. But since 

 it originally came from an entirely dififerent region (Wateree 

 River, South Carolina) it cannot be identified with certainty 

 and should be disregarded, at least for the present. 



U. mccstus Lea surely is this tipper Tennesee form of glans 

 (from French Broad River). The figure represents a very 

 large male ; but similar specimens have been found by Ortmann 

 in the French Broad drainage, fully agreeing with this in 

 all characters, including the proportional dimensions (height 

 of male, 58-63% of length; of females, 63-68%; diameter of 

 male 38-43% ; of female, 39-48% ; Lea's figures for height and 



