70 NEW UNIONID.E OF THE UNITED STATES. 



Remarlcs. — Two specimens only were received — one probably full grown, fi'om 

 which the figure is made, the other probably one-third grown. The former is no 

 doubt adult. It is nearly allied to Eitabrookianus, (nobis), and somewhat in outline 

 to ruhiginosiis . It is sulcate like the former. The young specimen has an indistinct 

 ray down the middle of the disks, the adult one a few indistinct rays near the beak. 

 The tips of the beaks of these two specimens are too imperfect to observe their undu- 

 lations. 



I name this after Mr. Meredith, a young student of natural history, to whose indus- 

 try I owe this and many other shells from the same habitat. 



Unio perradiatus. PL 6, fig. 215. 



Testa laevi, subtriangulari, inflata, postice obtuse biangulata, subinsequilaterali ; valvulis crassiusculis, pos- 

 tic6 crassioribus ; natibus subgrandibus, tuinidis et incurvis ; epidermide nitida, lutea et tota virido- 

 radiata ; dentibus cardinalibus parviusculis, valdd crenulatis, in utroque valvule duplicibus ; lateralibus 

 subbrevibus, lamellatis subcurvisque ; margarita alba et iridescente. 



Shell smooth, subtriangular, inflated, obtusely biangular behind, rather inequilate- 

 ral ; valves a little thick, thicker before ; beaks rather large, swollen and incurved ; 

 epidermis shining, yellow, with green rays over the whole disk ; cardinal teeth rather 

 small, very much crenulate, double in both valves ; lateral teeth rather short, lamellar 

 and curved ; nacre white and iridescent. 

 Proc. Acad. Nat. Sci. 1858, p. 40. 



Hah. — Florence, Alabama. Rev. George White. 



My cabinet and cabinet of Mr. White. 

 Diam. 1-2, Length 1-5, Breadth 2-3 inches. 



Shell smooth, subtriangular, inflated, obtusely biangular behind, rather inequi- 

 lateral ; substance of the shell a little thick, thicker before ; beaks rather large, 

 swollen, incurved ; ligament rather long, thick and dark brown ; epidermis shining, 

 yellow, with green rays over the whole disk ; umbonial slope raised, obtusely angular ; 

 posterior slope wide, subcordate, with a furrow in each valve from the beaks to the 

 margin ; cardinal teeth rather small, very much crenulate, double in both valves ; 

 lateral teeth rather short, lamellar and curved ; anterior cicatrices confluent, rather 

 large and well impressed; posterior cicatrices distinct, large and moderately im- 

 pressed ; dorsal cicatrices placed over the centre of the cavity of the beaks and across 

 the base of the cardinal tooth ; cavity of the shell deep and large ; cavity of the beaks 

 deep and obtusely angular ; nacre white and iridescent. 



Remarks. — I have seen but a single specimen of this species. It is very imperfect 

 about the beaks, and therefore the form of the undulations is not ascertained. It be- 

 longs to the group of which mnUiradiahis (nobis) may be considered the type, but it 

 difters in being more inflated and in not having an elliptical outline. 



