e 
Geology and Natural History. 319 
of the hills is very thinly and partially covered with “red earth,” 
mixed in varying proportions with vegetable matter. This scanty 
soil is fertile, if well used. en uncleared, it is covered with 
bush and forest trees. There are also sandy tracks termed “ pine- 
barrens,” where the bush suddenly disappears and the palmettos 
become fewer in number, though enough remain to exhibit an 
} 
northern and southern floras. The lowest portions of the flat 
grounds frequently nonkenn small brackish water or salt lakes. In 
the chalk-marsh of Andros Island, howev er, there is a freshwater 
lake, with three streams as its outlets; and it appears that, there i is 
no ele freshwater lake or stream in ahs Bahamas. 
There are large caverns in Long Cay and Rum Cay; a pr 
ply caverns are as numerous in the Bahama Islands as in the 
mudas; but so few extensive excay ations have nee made, that 
Ba cannot be positively affirmed. of the most 
striking objects in the topogra er of ue ae: is the very 
veep submarine valley, forming the gulf known as “the Tongue 
f the Oce ean,” nee runs into the Great Bahama Bank trom its 
ved ea end. The color of the water around the islands is usually 
G, &e., growing confusedly together without any other appar- 
ent order than that of accidental succession and accretion, both 
laterally and vertically. These are at times aided or even super 
seded by Serpule, &c., as seen in the serpuline reefs 
apt. Nelson si ‘out a few of the localities that exhibit most 
clearly the character, source, and mode of sagregation of ben 
materials of the ordinary Bahama rock, such as is formed 
the sea level; at the same time re ferring ‘the illustrative 
penimons in the ere Segiton' n, For peinne: ut 
ide : 
Point and W (specim o. 1) the shells o 
; re especially accompany th Jast 
Point (s ens Nos, 2 and 3) the sand is derived from corallines 
and nullipores; the finer sand ing often in ig, SN iggy sre 
spherical grains, phongh not so perfectly as at the 
(Specimen No. between Exuma and Lon he beac 
ear Charlotteville 1 Point (specimen No. 5) consists prineipally of 
dg ylvanica in various stages of Seung taatine f 
Hills (Caicos Group) the mass of Conch shells ( Strombus gigas) 
uffi 
rock, but an island several hundred feet in length. Along the N. 
Ww. beach at Gun Cay (specimen No. 8), a hard, coarse, stratified 
