GONIODASIS. 



279 



nated line onlj' formed in its immature state ; having increased to 

 four or five volutions the carina is no longer formed. — Say. 



The following are sj^nonymes : — 



Jlelania exilis. — Shell long and slender, composed of about eight 

 convex whorls ; apex pointed ; suture deep ; aperture narrow, elliptic, 

 equally curved on both sides ; labrum much advanced anteriorly. 



Habitat. — Kentucky and Ohio. 



Length, 'i of an inch. 



Observations. — More slender tlian ilf.siJnpZex, Say. — Ilaldeman. 



Jlelania ritfula.— Shell lengthened, conical, composed of eight 

 whorls, the four anterior of which are convex, and those of the apex 

 flat; suture well marked; spire twice the length of the -p- ggg 

 aperture; apex suddenly tapei-ed to a point; aperture 

 ovate, elliptic. 



Habitat. — Lake Pepin. 



Length, 1 inch. 



Observations. — Distinguished from 31. simplex by having 

 the peritreme level, and from 31. Virginica by the flat- 

 tened apex. — Haldeman. 



Melania Kirtlandiana. — Shell smooth, acutely conical, rather thick, 

 shining, horn-colored; spire elevated towards the apex, carinate; 

 sutures impressed; whorls nine, rather convex; aperture 

 small, elliptical, whitish. 



Habitat. — Richmond, Indiana: Duck Creek near Cincinnati 

 and Miami, Ohio : Little Miami. 

 Diameter, -30; length, -87 of an inch. 



Observations. — This is a finely formed, graceful species, 

 with an indistinct carina on the lower part of the whorls, 

 near the apex. The aperture is nearly one-third the length of 

 the shell. I name it after Professor Kirtland of Poland, 

 Ohio.— Zea. 



3Ielania inornata. — Shell moderate in size, rather solid, 

 ovately lanceolate, simple, yellowish-green, deeper below, 

 and paler at the sutures ; whorls eight, the apical ones cari- 

 nate, the last equal to two-fifths the length of the shell. Ap- 

 erture a third of the total length, narrowly lunate, subacute 

 before produced; columella narrow, white, with a calkis in front. 



Habitat. — Lorrain County, Ohio. 



Longitude, seven-eighths ; latitude, three-tenths poll. 



Fig. 540. 



Fiff. 541. 



