258 NEW UNIONID^, MELANID^, ETC., 



Eab.—Bvit\eY, Taylor Co., Georgia, Dr. H. M. Neisler. 



My cabinet and cabinet of Mr. Neisler. 

 Diam. -6, Length 1, Breadth 1-4 inch. 



Shell smooth, triangular, shining, rather inflated, inequilateral, angular behind, 

 round before ; substance of the shell somewhat thick ; thicker before ; beaks some- 

 what prominent, undulate at the tips; ligament very short and light brown; epider- 

 mis yellowish or brownish, obscurely rayed and with distant marks of growth on the 

 younger and more closely on the older portion ; umbonial slope somewhat raised and 

 obtusely angular ; posterior slope rather narrow, slightly carinate, with two darkish 

 lines on each valve from the beaks to the posterior margin ; cardinal teeth small, 

 oblique, somewhat compressed; lateral teeth rather long, oblique and corrugate; 

 anterior cicatrices distinct, rather small and well impressed ; posterior cicatrices con- 

 fluent, rather small and slightly impressed ; dorsal cicatrices placed above the centre 

 of the cavity of the beaks; cavity of the shell rather shallow; cavity of the beaks 

 shallow and obtusely angular ; nacre white or pale salmon and very iridescent. 



Remarks. — Seven specimens were sent by Dr. Neisler, among others, from Taylor 

 County. It is so nearly allied to striatulus (nobis) that at first I supposed it to be a 

 strong variety. On a more careful examination, I have no longer any doubt but that 

 it differs. It is more oblique, has not the transverse striae and differs in the undula- 

 tions of the beaks, which are more developed. The color of the epidermis is also of a 

 brighter yellow in the young. The nacre of amahilis is disposed to be of a dilute yel- 

 lowish salmon color. 'The older specimens have quite a dark brown epidermis, while 

 the younger are yellowish and brighter. After the third line of growth these lines 

 become much closer. The older specimens are much eroded at the beaks and then 

 they take, in a measure, the outlines o? i^jriformis (nobis). The younger ones remind 

 us otfavosiis (nobis), but this species differs in many respects from that, particularly 

 in the rays, which in amahilis are scarcely observable, even on the young specimens; 

 while on favosus they are strong and very beautiful. One of the specimens of amahilis 

 has perfect beaks, which show five subconcentric folds on the first growth. 



Unio Cromwellii. pi. 31, fig. 73. 



Testa Irevi, elliptica, subinflata, valde inrequilaterali, postice rotundata, antice rotunda ; valvulis 

 subtenuibus, antice crassiusculis ; natibus subprominentibus, ad apices concentrice plicatis ; 

 epidermide minute striata, fusca vol virenti, radiata ; dentibus cardinalibus parvis, compressis, 

 corrugatis, in utroque valvule duplicibus ; lateralibus sublongis subcurvisque ; margarita 

 purpurescente et valde iridescente. 



Shell smooth, elliptical, somewhat inflated, very inequilateral, rounded before and 

 round behind; valves rather thin, thicker before; beaks somewhat prominent. 



