132 NEW UNIONID^, MELANID^, ETC., 



GONIOBASIS SUBRHOMBICA. PI. 23, fig. 34. 



Testa subcarinata, subfasiformi, subtenui, tenebroso-oliva, estriata et evittata ; spira obtusa ; suturis 

 impressis; anfractibus quinis, planulatis, superne carinatis ; apertura grandi, rbomboidea, iutus 

 albida ; labro acuto, vix sinuoso ; columella tenui et aliquanto contorta. 



Shell subcarinate, subfusiform, rather thm, dark olive, without strio3 or bands; 

 spire obtuse ; sutures impressed ; whorls five, flattened, carinate above ; aperture 

 large, rhomboidal, whitish within; outer lip acute, scarcely sinuous; columella 

 thin and somewhat twisted. 



Operculum thin, brown, with the polar point near the left edge towards the base. 

 Proo. Acad. Nat. Sci., 1864, p. 111. 



Hah. — Hog Creek, North Georgia, J. Clark. 



My cabinet. 

 Diam. -26, Length '60 inch. 



Remarhs^ — I have about thirty specimens before me of this sj^ecies. It is closely 

 allied to Melania {Goniobasis) rliombica, Anth., and when I first received it I thought 

 it was merely a variety of that species. In getting typical specimens, however, of 

 that species from Mr. Anthony, I became perfectl}' satisfied that they were distinct. 

 Rhombica is decidedly carinate on all the whorls, is sharply so on the upper whorls, 

 is striate, as described by Mr. Anthony, and is of a light green color. Subrhombica, 

 on the contrary, is not carinate on the lower whorl, has no strise, and is of a dark 

 olive green. Two specimens among all those before me have obscure bands inside. 

 The aperture is about one-half the length of the shell. 



Rhombica is from Alabama. 



Goniobasis Cumberlandensis. PL 23, fig. 35. 



Testa Ijevi, acuminato-conoidea, subtenui, rufo-fusca; spira subelevata; suturis regulariter impressis; 

 anfractibus octonis, convexiusoulis ; apertura parviuscula, subrhomboidea, intus albida vel purpures- 

 cente ; labro acuto, parum sinuoso ; columella albida vel purpurea, infleota et contorta. 



Shell smooth, acuminately conical, rather thin, reddish brown ; spire somewhat 

 raised ; sutures regularly impressed ; whorls eight, somewhat convex ; aperture 

 rather small, subrhomboidal, whitish or purplish within ; outer lip acute, rather 

 sinuous ; columella whitish or purplish, bent in and twisted. 



Operculum ovate, dark brown, with the polar point on the left of the basal margin. 

 Proc. Acad. Nat. Sci., 1863, p. 155. 



Hob. — Gap Spring, Cumberland Gap and Bull Run, Major Lyon; Knoxville, 

 Tenn., Wm. Spillman, M. D. 



My cabinet and cabinets of Capt. Lyon and Dr. Spillman. 

 Diam. -25, Length -62 inch. 



