300 Miscellaneous. 



These ribs are crossed in the middle of each of the last three whorls 

 by other spiral ribs, of which there are three on the last, two on the 

 next, and one on the middle whorl. The spiral or transverse ribs are 

 only half the width and thickness of the longitudinal ribs. Base of 

 the last whorl smooth. Suture deep and distinct, giving the spire 

 rather a turreted appearance. Aperture oval, simple, contracted at 

 the upper angle and smooth within. There is a slight fold on the 

 pillar, forming behind it a small umbilicus. Length -jig, breadth -^ 

 of an inch. Somewhat resembles Odostomia pupa of Searles Wood 

 in markings, and Rissoa Zetlandica in form. 



Fusus Berniciensis. From the hooks on fishing lines in deep water, 



Rostellaria Pescar bonis. Sow. 



Scissurella crispata. Alive, adhering to stones like Emarginula. 

 The shell has no operculum, but it is to be regretted that Mr. Bar- 

 lee did not observe the animal. 



Tellina balaustina. One specimen, half- grown. 



Descriptions of new Freshwater Shells. By T. A. Conrad. 



The following new freshwater shells from Georgia were kindly 

 lent me for description by J. Hamilton Couper, Esq. 



Unio. 



U. securiformis . Suborbicular, thick, compressed ; valves slightly 

 convex ; umbo flattened, marked with obtuse, narrow, divaricated 

 plaits ; plaits on the lower half of the valves obscure and interrupted ; 

 umbonial slope rounded ; posterior slope with strong oblique plaits 

 towards the apex ; beaks eroded ; epidermis black ; within white ; 

 cardinal teeth large, direct, profoundly sulcated. 1-| : 1;^. 



Inhabits Flint River, Georgia. 



U. stagnalis. Widely elliptical, ventricose, rather thin ; towards 

 the posterior extremity very thin and fragile ; anteriorly regularly 

 rounded ; posteriorly somewhat pointed, with an acutely rounded ex- 

 tremity; basal margin regularly curved ; summits prominent, eroded; 

 posterior margin very oblique and nearly straight ; epidermis ochra- 

 ceous and olivaceous ; rays green, not very distinct on the middle 

 and anterior side, but more so posteriorly, some rather broad, others 

 linear ; posterior slope dark-coloured, rayed ; within white and highly 

 iridescent posteriorly ; cardinal teeth much compressed and oblique, 

 double in each valve ; lateral teeth very slightly curved, finely gra- 

 nulated. Z\. 



Inhabits mill-ponds ; Ogeechee River, Georgia. 



U. Ogeecheensis. Elliptical, thin, inflated ; posterior side some- 

 what pointed, extremity subangular ; valves slightly contracted from 

 beak to base ; summits rather prominent, decorticated, slightly un- 

 dulated ; epidermis ochraceous with interrupted green rays, some of 

 them broad; within white, highly iridescent posteriorly; cardinal 

 teeth oblique, compressed ; lateral teeth rectilinear. 3. 



Inhabits Ogeechee River, Georgia. 



Allied to the preceding, but has a lighter-coloured epidermis with 



