et 
326 Screntific Intelligence. 
the caoutchouc, but this supercrust was nowhere bent up into 
steep — or bold wrinkles thro ough the contraction in progress, 
was probably disturbance and mountain-making in the 
Green Monnidai region after the close of the Lower Silurian ; and 
it is possible that effects of the same disturbance will be found 
Archean and the close of the Cartineeams, making the antece- 
dent period of quiet, on the above estimate of time, nearly forty 
millions of years. Over the Rocky Mountain pes it is not yet 
proved that any great pect agaiad oceurre either of these 
not before the close of the acta 
(2.) The folds often have all the steeper inclinations facing 
in one direction and the less steep in the opposite, showing that the 
results of the pressure were unlike in the two opposite sealers 
The well known facts in the Appalachians, as first annou ry 
Professor neues abundantly illustrate this, and, also, pat in 
the Jura Moun 
The results shtainiod with the contracting | —— correspond 
one respect with rock-flexures, and it is a point not alway 
pcceed by those who spec culate on mountain- riuskiogs Tn 
mountain regions the flexures in the earth’s strata are not, with 
very rare exceptions, soahaunind by like flexures in the contract 
g crust ( : 
enough at the close of the Paleozoic, —. ~ sper yt were 
formed, to have made such narrow ben 
Itaparica, to the south of the entrance to the Rio person do 
Norte. It was explored by Mr. John Branner of the Geological 
mission. In shape and structure, as well as in the paucity 
of coral life upon it, this last agrees very closely with the Itaparica 
jae It — the trend of the shoes at a short distance from 
t, and between the reef and the shore there is an average dep 
coral growth. No sections were obtained giving us a clue to its 
