68 bafinesqtje's 



but an ombilic. Many sp. 1. 0. cuprea. Suboval, 4 spires, 

 smooth, brittle, diaphanous coppery, shining, opening very large. 

 In Kentucky. 



29. TRIODOPSIS, Raf. 1819. Diifer Helix, opening with 3 

 teeth. 2 above, 1 below, an ombilic. 1. Tr. lunula. Depressed, 

 mouth narrow with thick lips, ombilic lunulatcd. In Kentucky. 

 Forms S. G. menompliis. 



30. XOLOTREMA, Raf. 1819. Differ from the'last by no 

 ombilic, opening linear. 1. X clausa. Subdepressed, 5 spires a 

 little striated, opening almost hidden. I have many more land and 

 fluviatile univalves, too many to enumerate here ; but I add two 

 beautiful Agatinas from the south. 



31. Agatina VariegatajJiaf. 1820. Six spires, smooth, yellowish, 

 variegated with brown spots near the sutures, first spire with some 

 narrow coloured strias concentric Nearly two inches, from 

 Louisiana. 



32. Agatina Fuscata, Raf 1822. Eight spires, smooth, reddish 

 brown, with broad longitudinal black bands on the spires, of a lan- 

 ceolate flexuose shape. Over two inches. From Texas. Both col- 

 lected by Dr. Strong. 



YII. FOSSIL BIVALVE SHELLS. 



S3. Mytilus exotilus, Raf. 1820. Oblong oboval, minutely striated, 

 strias broader below, curved near the sides. Breadth two thirds of 

 length, thickness 4-9. From the limestone near Boon creek, Ken- 

 tucky, petrified, over 2 inches. 



34. APLEUROTIS, Raf. 1819, and tract of October, 1831. K 

 G. very near mytilus, but winged and perforated. 1. AjjV.pectenoides, 

 Raf. Oboval, upper valve convex striated, wing well marked, lower 

 valve flat, scarcely striated. Breadth 4-5 of the length, which is 

 over 2 inches. 2. Apl. pusilla, Raf. Oblique oboval, flattened, 

 minutely striated, wing sniall. Breadth | of the length, which is less 

 than one inch. Both. from Knobhills of Kentucky. 



36. OXISMA, Raf. 1819. K G. near Finna. Base truncate, 

 [4] 

 end gaping, equivalve, hinge lateral plicate on one valve, angular on 

 the other. 1. 0. bifida, Raf. Shell bifid by valves acute and gaping 

 before, outside black and rough, sides straight, length 3-8 of the 

 breadth, hardly one inch. Knobhills. 



3T. Terebratulites Eriensis, ^0.1 1818. Base smooth, remainder 



