PLATE LXXXI—Continued. 
Fig'. 31. Dorsal view of an internal cast of a narrow and elongate shell, in which the impression of the 
muscular platfoi'in of the brachial valve is sharply defined. 
Fig. 32. A gutta-percha impression made frcim the same specimen ; showing the collar or inverted lamella 
about the foramen, a portion of the dental plates and the form of the muscular platform. 
Upper Carboniferous limestone. /Southern Indiana. 
Figs. 33-3.1. Profile, dorsal and ventral views of a large and characteristic example ; showing the curvature 
of the valves, the broad concavity of the pedicle-valve and the reflexion of the anterior mar¬ 
gins ; also the oblique foraminal aperture. 
Upper Carbonifei'ous limestone. Harrison county, Missoun. 
DiELASMA, S[). ? 
Cardinal view of a specimen enlarged to show the oblique opening of the pedicle-passage and its 
cross-striated sui'face. X 3. 
An internal cast of the brachial valve ; showing the form and striation of the muscular platform. 
X 3. 
Chester group. Caldwell county, Kentuchy. 
Dielasma obovata, sp. nov. 
Figs. 38-40. Dorsal, profile and ventral views of a specimen having the aspect of D. formosa, but said to be 
from the Coal Measures. 
Coal Measures. Kentucky. 
Genus CKYPTONELLA, Hall. 
Page 286. 
Cryptonella subelliptica, sp. nov. 
Figs. 41-43. Dorsal, profile and ventral views of a lai’ge internal cast in iron-stone ; showing the form, con¬ 
tour and muscular scars of the brachial valve. 
Waverly group. /Sciotmnlle, Ohio. 
Fig. 36. 
Fig. 37. 
