| Review of Geinitz on the rocks and fossils of Nebraska. 179 
is too imperfect for satisfactory identification or to show ay re- 
liable characters for distinguishing it from forms in our - 
measures, 
Astarie gibbosa McCoy. Geinitz, ib., fig. 23. This agrees quite 
nearly with McCoy’s figure, but to establish positive specific iden- 
tity would require a comparison of specimens showing the hinge 
and interior, which might even show them to belong to different 
genera. They are probably both Edmondias, however, and look 
unlike Astarte. Dr. White finds them in the Upper Coal-meas- 
ures of Iowa. aes 
Astarte Nebrascensis (n. sp.), and A. Mortonensis Geinitz, ib., as 
Well as the form he figures A. Vallisnerianus King, have more 
the aspect of Astarte,; but the latter looks less like Prof. King’s 
figures than the form figured as a new species A. Nebrascensis. 
At any rate, specific identifications, and even generic references 
of such shells, can be admitted only provisionally, until the 
inge and interior is known. 
zodus ebscurus Sowerby, and /S. Rossicus de Vern. The 
forms figured under these narnes on plate I, resemble these Eu- 
ropean shells quite nearly; but it must be obvious that in a genus 
like this, in which species vary more or less in outline, and pre- 
Sent so few characters for identification, little reliance can be 
2 upon identifications from external characters only, espe- 
cially when the specimens were obtained at so widely distant 
Ws more elevated, and more ventricose beaks. Froma tracing 
of the type of Prof, Swallow's Cypricardia? Wheeleri, d scribed 
ftom the Missouri Coal-measures, it appears almost certain 
itis the same here figured under the name of S. obscurus. Young 
xamples of .S. alpina (=Dolabra? alpina Hall, Iowa Rep., pl. 29, 
t 2) the Lower Coal-measures, in some of its variations, 
on the middle and anteri 
