NATURAL SCIENCES OF PHILADELPHIA. 
139 
bus ; natibus prominentibus, tumidis ; epidermide miciante, vel lutea vel 
tenebroso-oliva ; eradiata ; margarita alba et iridescente. 
Hab. — Uphaupee Cr., Macon Co., Geo. W. Gesrier. 
Anodonta Gesnbrii. — Testa laevi, elliptica, valde inflata, postice sub-angulata, 
valde inasquilaterali ; valvulis subcrassis, natibus prominentibus, tumidis ; epi- 
dermide polita, vel viridi vel lutea, obsolete radiata ; margarita vel alba vel 
aurea et iridescente. 
Hab. — Uphaupee Cr., Macon Co., Alabama. W. Gesner, of Milledgeville. 
Georgia. 
Anodonta Dariensis. — Testa lasvi, elliptica, ventricosa, inaequilaterali, postice 
obtuse angulata ; valvulis subtenuibus, antice crassioribus ; natibus elevatis, 
tumidis, ad apices minute undulata ; epidermide tenebroso-oliva, striata, obso- 
lete radiata ; margarita coeruleo-aiba et iridescente. 
Hab. — Hopeton, near Darien, Geo., J. Hamilton Couper ; and Swift Creek, 
near Macon, Geo. ; Bishop Elliott, and J. C. Plant. 
Anodonta Danielsii. — Testa l^vi, elliptica, compressa, postice obtuse angu- 
lata, valde insequilaterali ; valvulis subtenuibus ; natibus prominulis, ad apices 
undulatis ; epidermide tenebroso-fusca, micante, obsolete radiata ; margarit.'i 
coeruleo-alba et iridescente. 
Hah. — Topeka, Kansas. Prof. Edward Daniels. 
Explorations under the War Department. — Explanations of a second editioii of a 
Geological Map of Nebraska and Kansas, based upon information obtained in 
an Expedition to the Black Hills, under the command of Lieut. G. K. WarreB, 
Top. Engr. 17. S. A. 
BY F. T. HAYDENj M. D. 
Geologist to the Expedition. / 
In May of 1857, by permission of the War Department, I prepared and read 
before the Academy of Natural Sciences at Philadelphia, a few brief notes on 
the geological structure of the vast region drained by the Missouri River, with, 
a section showing the different formations from Fort Benton to the mouth, of 
the Platte. The geology, as far as it was known at that time, was represented 
by colors, on a topographical map constructed by Lieut. Warren. Since that 
time the expedition to the Black Hills under his command, has brought back 
many additional facts and much new material, which render a second edition 
of the map necessary, and enables me not only to add some geological for- 
mations, not previously known to exist in the West, but to enlarge to a considera- 
ble extent the boundaries of others. In my notes explanatory of the geologi- 
cal portion of the map, I shall endeavor, as far as possible, to avoid the repeti- 
tion of material already made known, through numerous publications, 
in connection with Mr. Meek. A much larger surface might have been 
colored on the map with a good degree of confidence, but I have preferred to 
confine myself, for the most part, to the results of my own observations in the 
field, leaving the blank portions to be filled up by future explorations. 
The rocks of Nebraska, as far as they are at present known, are referrible 
to the following geological systems : 
I. Metamorphosed azoic rocks, including clear granite. 
II. Lower Silurian. (Potsdam standstone.) 
III. Devonian? 
IV. Carboniferous. 
V. Permian. 
VI. Jurassic. 
VII. Cretaceous, Upper, Middle and Lower (including Wealden ?) 
VIII. Tertiary. 
IX. Post Pliocene or Quaternary. 
1858.] 
