ALEXANDER AGASSIZ 437 
being his last paper upon the results of the explorations of 1891. The 
final report is beautifully illustrated with drawings made by A. M. 
Westergren. 
In the autumn of 1892 his friend Mr. John M. Forbes offered to 
place at his disposal his steam yacht Wild Duck, a sea-worthy little ves- 
sel 127 feet long upon the water line; and from January until April, 
1892, he cruised in this yacht, wandering for more than 4,500 miles 
among the Bahamas and off the Cuban coast, engaging in the study of 
the part which corals have played in the formation of these islands. 
On this and all subsequent expeditions he was accompanied by his son 
Maximilian, who was his father’s constant companion and friend, and 
who served as his photographer. The results of this voyage were pub- 
lished in 1894 in the “Bulletin” of the Museum of Comparative 
Zoology. 
He concludes that the Bahama Islands are composed of xolian rock, 
being formed of wind-blown fragments of shells and other limestone 
particles of animal origin which, after being blown upward above sea- 
level, have been agglutinated into rock by the agency of rain water. 
After being thus built up the islands subsided about 300 feet, and are 
now much smaller than they originally were, for the sea and atmos- 
pheric agencies have eroded them greatly. The present-day corals form 
a mere veneer over this submerged eolian rock and do not play a prom- 
inent part in forming the islands. The so-called “lagoons” of the 
Bahamas are merely parts of the interior of the islands which have 
been dissolved out under atmospheric agencies, rain, etc., and have 
been deepened by the action of the sea after the ocean water entered 
them. Hogsty Atoll he would regard as a plateau of submerged eolian 
rock surrounded by a rim which does not reach the surface and is pro- 
tected from marine erosion by a coating of modern corals. 
Five superimposed limestone terraces are seen at Cape Maysi and 
can be traced for a considerable distance along the Cuban coast. The 
lowermost of these terraces is raised only about twenty feet above sea 
level and is clearly an elevated coral reef, but the older and higher 
terraces he is inclined to regard as being of limestone covered only by 
a mere veneer of corals or containing only a few scattered coral heads 
and not true elevated coral reefs. 
The peculiar flask-shaped harbors of Cuba with their narrow en- 
trances and broad lagoons interested him greatly, and he decided that 
when the land was elevated these depressions had been leached out in 
the limestone by the action of streams in the drainage areas of the val- 
leys, and when the land afterwards sank the broad valleys were sub- 
merged, with only a deep narrow entrance connecting them with the 
sea. Yumuri Valley would constitute just such a harbor were it sub- 
merged beneath the sea. 
