58 PROCEEDINGS OP THE ACADEMY OF [188c 



A NEW UNIO FROM FLORIDA. 

 BY BERLIN H. WRIGHT. 



TJnii Cunningham i. Plate I, figs. 1-4. 



Shell ovate, ventricose and very inequilateral, smooth, inter- 

 rupted by numerous irregular, undulating lines of growth, causing 

 a scaly appearance near the margins, and very highly polished 

 above ; substance of shell very thick, constricted posteriorly, 

 angular behind and truncated before ; ligament margin moderately 

 arcuate and angular at the terminus (tip) ; posterior margin 

 wedge-shaped and slightly acuminate ; ligamental area elongately 

 cordiform and wide, nearl}^ forming a plane in old individuals ; 

 umbonal slope subangular from beak to margin ; anterior margin 

 angular above and somewhat abruptly rounded beneath ; basal 

 margin emarginate posteriori}^ in the males and uniformly curved 

 in the females ; epidermis usually dark chestnut or reddish brown, 

 interspersed with marginal bands of light horn-color; occasionally 

 the entire shell is of uniform light horn-color, wrinkled and entirely 

 destitute of rays ; greatest diameter near the middle of the umbos ; 

 beaks eroded and obtuse ; umbo broad and flattened ; nacre usually 

 a delicate pink : occasionally white ; cardinal and lateral teeth both 

 single in the right and double in the left valve, lateral teeth short, 

 slightly and uniformly curved and separated from the cardinal 

 teeth by a space equal to onedialf of their own length ; cavity of 

 the shell and beak both shallow ; dorsal cicatrices five and situated 

 above the centre of the cavity of the beak ; distinct anterior and 

 confluent posterior cicatrices ; ventral cicatrix usually present and 

 placed anterior to the centre of the cavity of tiie shell. 



Habitat. — -Lakes of Sumter County, Florida. 



This beautiful shell belongs near U. Buckleyi Lea, from which 

 it differs in being strictly ra^less in all stages of its growth, greater 

 diameter, more angular anteriorly above and more abruptly rounded 

 beneath, broader and flatter umbos and more abrupt posterior slope. 

 The cardinal teeth are much heavier and not as oblique as in 

 U. Buckleyi^ A large suite of the shells was sent to me by Mr. 

 T. L. Cunningham, of Yalalia, Sumter County, Florida, in whose 

 honor we name it. 



Plate I, fig. 1, Unio Llaaiiinghami, old unile ; ~', full-giovvii iLinale ; 

 3, old male ; 4, young" male. 



