652 BOWMAN— ECOLOGY AND 



on plant tissues, and Warming/^*^ Haberlandt,^^^ Karsten and others 

 who have all emphasized some special features of this ecologic 

 relation. 



The general impression of a mangrove swamp is very aptly 

 described by Warming (loc. cit.) : "The bottoms of the crowns of 

 the trees are usually truncate and stand a small distance above the 

 water, and beneath them are seen, where i^/n'r'o/'/zora-vegetation 

 forms the outermost fringe of vegetation, a tangle of countless 

 brown roots more or less clothed with algae. The soil, which in 

 places is not covered with water at low tide, is soft, deep black mud, 

 full of rotting, stinking organic bodies in which bacteria abound. 

 The water between the trees may be covered with dirty film and 

 bubbles of gas rising from the bottom burst at the surface." One 

 may also add that the air is usually thickly filled with voracious 

 mosquitoes. 



In spite of this rather unpleasant, but truthful description, the 

 mangrove formation holds a great many features of interest for the 

 ecologist, as Karsten^^- says in describing the mangrove swamps of 

 the Malay Archipelago — " Es ist ein Vegetationsbild von seltener 

 Einformigheit besonders fiir an tropischen Formenreichtum 

 gewohnte Augen und doch giebt es wohl wenige Gebiete, die bei 

 naherer Bekanntschaft eine solche Fiille von interessanten Formen 

 und Beziehungen zeigen.'' This uniformity to which Karsten refers 

 in the oriental mangrove consists of nine widely diverse families, 

 representing twenty-one species. Our American mangrove swamps, 

 however, are much more "uniform" than this. Harshberger has 

 summarized the species in the various kinds of mangrove thickets 

 {loc. cit., 144, p. yy) as they occur on the Peninsula of Florida for 

 the most part with brief notes on the vegetation of the Keys. The 

 whole aggregation of species which grow in all the types of man- 

 grove formations, whether it be along the rivers, bays or open sea, 

 on islands or everglades, embrace about twenty-eight species, in- 

 cluding pteridophytes, floating aquatic plants, epiphytic lichens, etc. 

 The trees of the typical mangrove habit, that is, those plants which 



loo Warming, Eug., " CEcology of Plants," tr. Vahl, Groom and Balfour, 

 Oxford, 1909, p. 234. 



1"! Haberlandt, G., " Eine Botanische Tropenreise," 1893, p. 182. 

 ■•" Karsten, G., loc. cit., p. 3. 



