AMERICAN AND WEST INDIAN FAUNA AND FLORA. 113 
of the Isthmus of Darien, of Panama, and of Nicaragua. Cen- 
tral America and northern South America at that time must 
have been a series of large islands, with passages leading 
between them from the Pacific into the Caribbean.' 
It is further interesting to speculate on what must have 
become of the equatorial current, or rather of the current pro- 
duced by the northeast trades. The water banking up against 
the two large islands, then forming the Caribbean Islands, 
must, of course, have been deflected north, have swept round 
the northern shores of the Virgin Islands, Porto Rico, apd 
Hayti, and poured into the western basin of the Caribbean 
Sea, through the passage between Hayti and Cuba. This water 
was forced into a sort of funnel, by the five-hundred-fathom 
line, which constituted the southern line of the great Bahama 
Island, and connected nearly the whole of the Bahamas with 
Cuba, forming thus a barrier to the western flow of the equa- 
torial current; this current must, therefore, for the greater 
part, have been deflected north, and either swept in a north- 
easterly direction, as the Guif Stream now does, or round the 
north end of the Bahamas across Florida, which did not then 
exist, across the Gulf of Mexico, and into the Pacific over the 
Isthmus of Tehuantepec. 
While undoubtedly the soundings indicate clearly the nature 
of the submarine topography, it by no means follows that this 
ancient land connection did exist as has been sketched above. 
At the time when the larger West India Islands were formed 
and elevated above the level of the sea, they may have been 
raised as one gigantic submarine plateau of irregular shape, in 
which were ы the Bahamas, Florida, Cuba, : San Domingo, 
Porto Rico, and the Virgin Islands. Exactly what portions 
rose above the level of the sea at that time it is difficult to 
determine, and it may be that at that period the islands, while 
larger perhaps than they are now, may still have been the same 
in ен having since been емы" in size by denudation, 
while the каны between them have been widened. 
1 We should bear in mind that the India Islands existed, thus leaving a free 
Windward Islands were probably raised access to the Pacific up to that time. 
long after the range of the greater West 
