MUSEUM OF COMPARATIVE ZOOLOGY. 269 
twenty feet high (one hundred and seventy feet above the sea) worn out 
of the lower part of the old white limestone. Its sides are vertical in 
most places; and inaccessible. This cliff is in turn surmounted by another 
bench (No. 2), which was likewise formerly an old beach level, from 
which any remnant of the deposit that may have once existed has been 
eroded. It is covered by a dense growth of vegetation. The river 
cafion which cuts across these cliffs and benches shows that they are 
not elevated built-up coral reefs, but are clearly cut sea terraces in the 
old limestone. The second bench is about a hundred feet in width, and 
abuts against a second vertical cliff, the summit of which is nearly as 
high as that of the first one, or about three hundred and fifty feet above 
the sea. The level bench (No. 3) mounting this cliff is similar in appear- 
ance to No. 2. 
This last bench in turn abuts against a third and uppermost escarp- 
ment of the highland, which terminates at a height of from five hundred 
to six hundred feet in the irregular upland plain forming the fourth 
level above the sea. 
The Cuchilla Level. — This fourth level is the general upland plain as 
it appears from the sea, and represents the old land from which was 
carved the group of cliffs above described. This highest escarpment 
forms a comparatively unbroken plateau at the eastern end of the 
island, overlooking the sea, but westward the increasing drainage cuts 
it more and more into numerous serrated hills known as the Cuchillas, 
or ‘‘ Knives,” whose summits have a general culmination of from five 
hundred to six hundred feet, and are clearly remnants of the Yumuri 
Plateau. These Cuchillas form a very conspicuous coast feature from 
Nuevitas to the east end of the island. 
The Yunque, or Higher Level. — A single glance at the peculiar iso- 
lated mountain known as the Yunque, or Anvil, situated six miles west 
of Baracoa, is sufficient to show that its sub-level summit is the remnant 
of an ancient higher level than that represented by the Cuchillas.1_ This 
is a magnificent butte, whose summit is put upon the pilot chart at 
eighteen hundred feet, and so estimated by Crosby. The summit is an 
ovoid mesa, which is apparently level, but which really shows deeply 
carved drainage ways and ancient topography indicating long exposure. 
The upper portion is composed of a mass of the older tertiary rocks one 
‘thousand feet in thickness, whose perimeter is an almost inaccessible 
cliff. This rests upon a base composed of the metamorphic rocks of the 
1 A. Agassiz, Bull. Mus. Comp. Zool., Vol. XX VI. No. 1, Plate XLI. 
2 Op. cit. 
