172 COLONIAL REPORTS MISCELLANEOUS. 



(ft.) Swamp Forests, the trees composing which are adapted to 

 growth in stagnant water. 



(c.) Mangrove Swamp Forests. - - This is a formation that is 

 confined to tropical shores where the climate is hot and humid. 

 The plants composing it are restricted to 1 the area comprised 

 between the limits of high and low tide, where the water is not 

 otherwise much agitated by constant strong winds and currents. 

 They have adapted themselves to growth in a salty stratum that is 

 alternately flooded by sea water and exposed to the air by the 

 fluctuations of the tide. They are characterised by their stilt- 

 like roots and the possession in the latter of pneurnatophores 

 and other devices for absorbing oxygen and transporting it to 

 such subterranean parts of the trees as may require it. 



Less important edaphic formations are represented by rock 

 plants (Lithophytes). 



Tropical W<ooilIanJ , so far as it is dependent on climate and 

 not on the effects of the soil, may be divided into the following 

 four kinds :- 



(1.) The liain Forest, or the moist tropical evergreen forest of 

 Indian foresters. 



It is an evergreen forest, hyyrophilous in character, with an 

 average height of more than one hundred feet, frequently much 

 taller. It is rich in thick-stemmed lianes and in woody as w r ell 

 as herbaceous epiphytes, and is associated with a constantly or 

 u early constantly moist climate with precipitations more or less 

 throughout the year, and with a dry season of short duration 

 that is frequently interrupted by showers of rain. 



<(2.) The Monsoon Forest, or mixed deciduous forest of Indian 

 foresters. 



It is more or less leafless during the dry season, especially 

 towards its termination, is tropophilous in character, usually less 

 lofty than rain forest: rich in woody lianes and rich in 

 herbaceous, but poor in woody, epiphytes. It is associated with 

 a climate in which a more or less copious rainfall is followed by 

 a well-marked prolonged dry season. 



(3.) Savannah Forest, the open deciduous forest of Indian 

 foresters. 



It is more or less leafless during the dry season, and but rarely 

 evergreen, is xerophilous in character, of less height than the two 

 preceding types, park-like, very poor in underwood, lianes, and 

 epiphytes, and //<// in terrestrial herbs, especially grasses. The 

 corresponding climate is one that favours grassland, but not to 

 the 'extent of excluding tree-growth in a pronounced degree. 



(4.) Thorn Forest. --It generally resembles savannah forest, 

 but is even more xerophilous in character; is very rich in under- 

 wood and thorn plants ; poor in terrestrial herbs, especially 

 l/nisscs, and usually has no epiphytes. The formation corres- 

 ponds to a dry climate with an absence of precipitations during 

 the vegetative season of the grasses. 



In accordance with transition's between the various climates 

 the above types are often connected by intermediate forms. The 



