GEOLOGY OF PERU—ADAMS. 411 
ean have taken place during ‘three hundred and fifty years as is 
shown by the position of Indian tumuli. He called attention to how 
shells may be transported inland by human agencies, by birds, winds, 
and drifting sands, and advises caution in accepting the mere pres- 
ence of shells as a proof of elevation. 
OBSERVATIONS IN NORTHERN CHILE BY ALEXANDER AGASSIZ AND lL. EF. PouRTALES. 
In line with the statements by Lieutenant Freyer it may be noted 
that in northern Chile, in a ravine 20 miles inland from Pisagua at 
Beringuela (at Tilibiche), at an elevation of 2,900-8,000 feet, “ recent 
corals” were found by Agassiz, who says that they indicate an 
inland sea connected with the Pacific Ocean, and that there is ac- 
cordingly reason to believe that the continent has been raised “ within 
a comparatively recent period.” 
The corals were described by Pourtales. It is stated that they 
were fossilized into a compact limestone and consisted of two new 
species. One was referred to a genus not represented in any lower 
strata than the Tertiary, and is not now living on the Pacific coast 
of America. The other species was referred to a genus which had 
up to that time been described only from Jurassic and Triassic 
formations. 
The writer wishes to call attention to the fact that the fossils do 
not date the “ comparatively recent period ” and do not furnish evi- 
dence which is more convincing than the relations of the Tertiary 
sediments, which are widely distributed in the coast region. 
Rarw RECONNAISSANCE OF THE TERTIARY AND QUATERNARY OF THE 
Coast. 
The writer in traveling through the coast of Peru studying the 
geology in relation to the underground waters, observed the occur- 
rence and distribution of the Tertiary formations in so far as was 
possible in the time allotted to his work, and has outlined the occur- 
rence of the formations in the bulletins by him published by the Corps 
of Engineers of Mines of Peru. From what he has written the 
following summary, which includes a few modifications, is presented 
with the hope that future observers may use it to correct and amplify 
a knowledge of the subject. 
TERTIARY OF THE NORTHERN COASTAL PLAIN. 
The Amotape formation. 
This name was given to the formations which are exposed near 
the village of Amotape, which is situated in the valley of the Chira 
River and is particularly well seen in the western end of the Brea 
