HILL: GEOLOGY OF THE ISTHMUS OF PANAMA. 
The Island of Cano . . IN oW UE SERENA 4 
SC is Point and the Gulf of сора б mega te 
Evidence of former Extent of Land on Pacific Side 
Parr IV. — A CONTINENTAL SECTION Across Совта Rica . 
Salient Features of the Costa Rican Section. . . . . oS 
Foantiror olihe Puin Gomte Us eure Қ ara уже 
'The San Mateo Peneplain i 
The socalled Boulder Glas rococo as Ta ead 
"The SOUR NANJO E E E ИНЕТе 
Central Volcanic Plateau . pales ake Weeds 
Ancient Bolsons of the Plateau Region . 
The Cretaceous Rocks of San Miguel . . . . . .« . . 
Old Voleanie Rocks of the San José Basin 
Thes pntag BANDE а asan s. op t PEE 3% 
Ascent of Irazu Volcano . . T" 
Peculiar Loess-like Deposits of the Slopes Gë: 
Report of Microscopic Study thereon by H. w. Turner. 
The Crater of Irazu and the Light it throws on the Origin of the 
Boulder Clays . . . Т ЧИНУ РИЧИ" 
Descent of the Atlantic Coast . ° қаттық 
Upturned Tertiary Sediments of the Atlantic Const ANE 
The Probable Occurrence of Granite at Siquieres 
The Coastal Region, and its Resemblance to the Isthmus at 
OLO oca PN Lt ar А 
The Pliocene Localities of Gabb е 
Comparison of the Panama and Costa Кіса Sections 
'Tabular Statement of Formations and Events 
Coal in the Isthmian Tertiary . 
Parr V. — Tap UNION OF THE CoxTINENTS, AND THE PROBLEMS OF 
THE STRAITS 
Résumé of Scientific Opinion concerning Periods of Continental Separa- 
tion and Union 
Résumé of the Known Geology of the Tropical American Mainland 
Incompleteness of Exploration . . e, QS 
Older Granitic Axes of the Caribbean Region. 
Known Paleozoic Strata 
The Older Mesozoic . . Coe VE VON Ты. 
Absence of Jurassic Sedimentary Rocks 
The Cretaceous Strata è 
The Marine Tertiary 
Formations composed of Sea Débris 
Land derived Littoral Deposits i 
Older Tertiary Littoral of the Gulf and Caribbean 
Guatemala, Chiapas, and Yucatan jeu 
Pliocene Formations . . . . . . 
Pleistocene and Recent 
Diastrophism of the Tropical American M: inland. ` 
Predominance of the East and West Orogenic Trends 
Evidence of the Existence of a Pre-Tertiary Orogenic Complex 
роста OF IGNEOUS ООУ to maw KEE RER 
Evidences of Pre-Tertiary Vulcanism ZE 
The Date of Post-Eocene “ Syenitic ” Intrusions ; тан ер 
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