FLORIDA REEFS. 



It had been stated that the reefs consisted solely of living corals ; and, 

 indeed, this report is true of the outer reef, which is called by all the inhabi- 

 tants of Florida " the reef' -par excellence, and is unfounded only with regard 

 to those few islands which rise above the surface of the sea at Sand Key 

 and the Sambos. Others, who had noticed only the larger accumulations 

 of coral fragments which occur on the shores of some of the islands forming 

 part of the Florida Reef, had reported the islands to be formed of coral 

 rocks ; while some who had perhaps observed the extensive excava- 

 tions made around Key West have told us only of the existence of 

 oolitic and compact rocks, almost destitute of corals or other remains 

 of animal life ; and from still other localities comes the opinion, that the 

 rocks consist of nothing but more or less disintegrated shells, cemented 

 together. 



Animal Life. 



This fulness and variety of animal life is particularly obvious within the 

 boundaries of coral fields, the natural limits assigned to the growth of these 

 animals being those in which animals of other classes range in greater 

 profusion, and the coral reefs themselves also affording very favorable 

 circumstances for the display of numerous living forms. Hence the extraor- 

 dinary assemblage of all classes of animals upon the reef, where, besides 

 those particular kinds of corals which contribute largely to its formation, 

 we find upon it, or on the foundation from which it rises, a great variety 

 of other corals, which, though too insignificant in size to take a conspicuous 

 part in building up these extensive accumulations of organic lime-rock, 

 add none the less their small share in the work, contributing especially 

 to fill up the vacant spaces left by the more rapid and durable growth 

 of the larger kinds. They are to the giants of the reef what the more 

 slender plants are to the lords of the forest, adding the elegance and 

 delicacy of slighter forms to the strength, power, and durability of their 

 loftier companions. 



But besides the stony corals, we find in the reef a great variety of soft 

 polyps, either attached to the surface of dead corals, dead shells, or of the 

 naked rock, or boring into the coral sand and mud. 



A variety of Medusa nurses arise everywhere, either as delicately branch- 

 ing tufts or as permanently attached Medusae from the same . foundation. 

 Their free progeny may be seen floating quietly in myriads in the waters 

 above. 



