146 



I have seen, excepting in this respect even M. suhglohosa, nob.. 

 and especially P. intertexta, nob., of which latter, in fact, I at first 

 supposed it to be the young, in consequence of its rotundity and 

 the similarity of its capillary lines ; but inasmuch as the number 

 of its whirls is nearly the same, whilst the magnitude differs so 

 greatly, I have separated it as a different species. 



Paludina intertexta. — Shell subglobose, yellowish-green or 

 brownish, wrinkled, and with minute, very numerous, obsolete re- 

 volving, deciduous lines : spire depressed conic, obtuse, truncated^ 

 eroded at tip : volutions nearly four : suture rather deeply indented : 

 umbilicus closed by the lateral extension of the columella. 



Greatest breadth, from four-fifths to one inch ; length about the 

 same. Inhabits Louisiana. 



We collected many of these shells in the marshes near New 

 Orleans and on the banks of the Carondelet canal. It is remarka- 

 ble for its globular form and for the numerous obsolete lines which 

 seem like equidistant deciduous corrugations of the epidermis, 

 having no effect whatever in modifying the calcareous surface, upon 

 which it exhibits no trace. 



Paludina elongata, Swainson. — Capt. Leconte presented me 

 with a shell which, he informed me, he found in the river St. 

 John, Florida. I described it nearly four years since under the 

 name of multiUneata ; but, recently, being about to publish it, on 

 a more attentive examination and comparison with a specimen of 

 the elongata from Calcutta, given to me by Mr. Hyde of Phila- 

 delphia, I have concluded that it varies from that specimen only 

 in having the umbilicus a little smaller. 



Paludina subpurpurea. — Shell oblong, subovate, olivaceous, 

 with a tinge of purple more or less intense, sometimes hardly per- 

 ceptible : spire rather obtuse, terminating convexly : whirls five, 

 wrinkled, equally convex : suture impressed, but not very pro- 

 foundly : aperture much widest in the middle, narrower above : 

 within glaucous, somewhat perlaceous : labrum rectilinear from the 

 middle upwards : umbilicus none. 



Length, about one inch ; greatest breadth, four-fifths of an inch. 



An inhabitant of Fox river, an arm of the Wabash. It is very- 

 distinct from any other species I have seen. The labrum exhibit? 

 no curvature from the middle almost to its j unction with the penul- 

 timate volution. 



