FREE INSTITUTE OF SCIENCE 



VEGETATION OF SOUTH FLORIDA 



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group is composed of cryptophytes characterized by their dormant buds being 

 subterranean, or sub-aquatic. They include aquatic and marsh plants (helo- 

 phytes), denoted by HH., and geophytes, denoted by G. The therophytes 

 (Th.) are annual plants that live in the unfavorable season as seeds. Finally 

 there are the stem succulents (S.) and the epiphytes (E.). 



An attempt has been made to group the native species of the Miami region, 

 the Florida keys and the pine-barren region of New Jersey under the above 

 growth forms, but this has been no easy task, because our knowledge of the 

 underground parts of many species is incomplete. It is, therefore, probable 

 that mistakes have been made. Some of these mistakes will neutralize each 

 other, but other errors are unavoidable when the descriptions and herbarium 

 sheets do not enable the student to reach determinative conclusions. The 

 percentages of the different growth forms in a region arranged in a series, or 

 gamut, gives a picture, or spectrum, in the words of Raunkiaer: "Ich werde 

 deshalb der Kiirzes halben im folgenden eine solche statistich-biologische 

 Uebersicht als Spektrum bezeichnen, als biologisches Spektrum oder Pflanzen- 

 klimaspektrum. " He has worked out theoretically a normal spectrum, 

 which is given in the adjoined table. With this normal spectrum, other 

 spectra can be compared. Under Ph. for St. Thomas and St. John islands, for 

 the Seychelles, Aden and the Normal Spectrum, the percentages are arranged 

 as MM., M. and N., i. e., megaphanerophytes, microphanerophytes and nano- 

 phanerophytes. It will be noticed, that in the Miami flora the hemicrypto- 

 phytes are the most abundant, followed by the phanerophytes, the therophytes 

 and the chamsphytes. In the flora of the Florida Keys, the phanerophytes 

 preponderate, followed by the chamaephytes (20%), therophytes (20%) and 

 the hemicryptophytes. 



* Paulsen, Ove: Studies on the Vegetation of the Transcaspian Lowlands, 1912: 135-173. 



