262 IN LOWER FLORIDA WILDS 



distinctly marked off from the rest, but in the 

 hotter regions trees make a growth whenever con- 

 ditions are favorable, and the layers of wood are 

 not necessarily annual and are often ill defined. 

 It is probable that the mangrove, in wet situations, 

 makes but a single growth in a year, but its layers 

 of wood are not well indicated. However, after 

 carefully studying sections of these large trees I 

 have placed their minimum age at a hundred 

 years. If I am right we have evidence of a 

 subsidence within the last century that may be 

 measured in inches. 



A walk along one of our mangrove shores, if 

 scrambling and falling among the roots may be 

 so called, is extremely interesting. On a recent 

 "stroll" I made note of the following flotsam 

 caught among the roots : leaves in great quantity 

 and variety, especially those of Thalassia (mana- 

 tee grass) and Cymodoce (turtle grass), both 

 erroneously called seaweed. The bulky masses of 

 these contribute greatly towards the building up 

 of the land: trunks and branches of trees, saw 

 logs, pieces of wood, some from, or parts of, vessels: 

 part of a chair, slabs from a sawmill, a number of 

 coconuts and other large seeds, a part of a saddle, 



