100 Journal of the Mitchell Society [Jime 



up of about a do/en larger islands, which are mostly bounded by the 

 Everglades on two sides and separated from each other by narrow 

 channel-like intersecting prairies. The Long Key group has a much 

 smaller area than the Biscayne pineland. It consists of about five 

 larger islands and a few smaller ones. Both groups are of limestone, 

 and they are slightly elevated above the Everglades. The rock is 

 rather porous and the softer spots of the almost universally exposed 

 surface -have been eroded, mostly by leaching out, so as to form a 

 surface honeycombed with all sizes of cavities having very ragged 

 and sharp edges. These limestone islands are almost completely for- 

 ested with the Caribean-pine {Pimis caribaea) which grows nearly 

 everywhere on the exposed rock. However, the pine-woods, or pine- 

 lands, are interrupted here and there by hammocks or areas of hard- 

 wood shrubs and trees, some areas small and some much larger, al- 

 though all taken together these comprise but a very small percentage 

 of the region under consideration. The hammocks may be divided 

 into two groups ; first, the high pineland hammocks which are islands 

 or colonies of hardwood trees in the pine-woods. They are dry except 

 for the water contained in deep lime-sinks and in the humid air. 

 They number about a score. Second, are the low pineland ham- 

 mocks, indefinite in number and situated along the boundary line of 

 the pinelands and the Everglades proper and prairies. These are 

 usually high and dry towards the pine-woods and low and wet along 

 the Everglades or prairies. 



The ratio of pineland ferns to hammock ferns seems astonishingly 

 small. There are only three kinds of ferns that may be considered 

 naturally pineland plants. Even two of these ferns will spring up in 

 clearings in hammocks which have been partly destroyed either by 

 nature or by man. The other forty-eight species are hammock plants. 

 Their habit ranges from the stiffest to the most graceful and their 

 structure from the coarsest to the most delicate. The pineland species 

 are strictly terrestrial in habit. The hammock kinds are to a great 

 extent epiphytic. 



The hammocks of the Biscayne pineland are rich repositories of 

 ferns. The trees are nearly all evergreen. More abundant are : 

 pigeon-plum (Coccolohis), devil's claws (Pisonia), blolly (Tornihia), 

 cherry (Laurocerasus) , wild-tamarind {Lijsiloma), Jamaica-dogwood 

 {Ichthyometkia) , coral-bean (Erythrina), torch-wood {Amyris), bit- 

 terwood (Simarouha), gumbo-limbo {Elaphrium), Guiana-plum 



