76 DONS. — DU 4 AVRIL AU 21 JUIN 1887 . 
L. E. Hicks. — Preliminary geological map of thaï portion of Nebraska east 
of the 98 th. meridian, 2IG. 
— The permian formation In Nebraska, 216. 
L. T. Hicks. — Some typical well-sections in Nebraska, 217. 
L E. Hicks. — The Lincoln salt-basin, 219. 
E. W. Claypole. — Preliminary note on some fossil wood from the carbonife- 
rous rocks of Ohio, 219. 
Chas. D. Walcott. — Cambrian âge oftbe roofing slates of Granville, Washing- 
ton Co. N. Y., 220. 
Julius Pohlmen. — The Niagara gorge, 221. 
R. S. Woodward. — On the rate of recession ofthe Niagara Falls at Shownby 
the results of a recent survey222. 
G. K. Gilbert. — The place of Niagara Falls in géologie history, 222. 
E. W. Claypole. — Bull'alo and Chicago, 224. 
W. M. Davis. — Mechanical origin of the triassic raonoclinal In the Connec- 
ticut valley, 224. 
G. K. Gilbert. — Some new géologie wrink les, 227. 
H. S. Williams. — The Strophomenidae ; Apalacntological study of the me 
thod of initiation of généra and species, 227. 
Eugène N. S. Ringueberg. — A trilobite track illustreting one made of pro- 
gression of the Trilobites, 228 . 
E. W. Claypole. — The deep well at Akron. Ohio, 228 . 
Frederick J. H. Merrill. — On some dynamic efliets of the lee sheet, 228. 
Théo B. Coinstock. — Venis of sont west Colorado, 229. 
George Kunz. — Remarkable occurrence ofrock crystal in the United State, 229. 
Wm. H. Pitt. — Remarkable impressions in syenite, 230. 
John Dickinson. — Remarks on the « petrilled forest » of Arizona, 230. 
Irving P. Bishop. — On certain limestones of Columbia Co, N. Y. and their 
relations to the States of the taconic System and the Shales of the Hudson river 
group, 231. 
I. Kosl. — Geology of Florida, 231. 
B. K. Emerson. — Preliminary note on the succession of the crystalline rocks 
and their varions degrees of metamorphism in the Connecticut river région, 23i. 
B. K. Emerson. — The âge and cause of the gorges eut strongh stthe trap ridges 
by the Connectitcut and its tributaries. 
Théo. B. Comstock. — Remarkable extinct geyser basin in Southwest Colo- 
rado, 232. 
— Super metamorphism ; its actualistyinducing causes 
and general efl'ects, 232. 
— Peculiarities ofthe drift of the Rocky Mountains, 233. 
B. K. Emerson. — The Holijoke range of the connecticut, 233. 
J. C. White (Title). — The criticism of the anticlinal theory of naturel gas, 233. 
J. C. Smock. — Note on the archaean rocks of the Highlands east of the Hud- 
son river in New York, 234. 
J. D. Dana. — Fossils from the taconic, 234. 
W. B. Dwight (Title). — Palaeontological observations on the limestone of the 
taconic sériés of Canaan, Columbia Go. N. Y. 
W. J. G. Mc Gee. — (Title) Quatenary phenomena about the head of Chesa- 
peake Bay, 234 . 
W. J. Mc Gee. — Topography about the head of Chesapeake Bay, 234. 
