THE FLORA OF GUIANA AND TRINIDAD 23 



These included species of Polypodium and Vittaria. This poverty of 

 the fern flora is quite in accord with the account given by Spruce of 

 the forests of the lower Amazon. 



Through the kindness of Dr. Cramer, the director of agriculture, 

 and other members of the scientific staff, an opportunity was afforded 

 of visiting a number of the most characteristic regions within reach of 

 Paramaribo, and an excellent idea was thus obtained of the more salient 

 features of the flora of this region. Excursions were made up the 

 Surinam Eiver and some of its tributaries, as well as to one of the 

 characteristic " savannas " occasionally met with in lower Surinam. 



Except in the immediate vicinity of Paramaribo there are no roads, 

 and communication (except for one line of railway) is almost entirely 

 by means of boats, which ply along the rivers, creeks and canals with 

 which the whole country is intersected. 



Owing to the flatness of the country, the tide extends for a long 

 way up the larger streams, and these rivers are everywhere bordered by 

 an impenetrable mangrove swamp, in the lower reaches of the rivers 

 composed almost exclusively of Rhizophora mangle, but higher up, where 

 the salinity of the water is less, the Ehizophora is gradually replaced by 

 Avicennia nitida, which sometimes becomes a large tree, whose aerial 

 roots often develop from the upper branches and reach an enormous 

 length. Back of the mangrove belt there sometimes occur slightly 

 elevated ridges upon which the largest trees grow. 



Nearly all of the cultivated land in lower Surinam has been re- 

 claimed by building dykes, and the old sluice gates, two or three 

 hundred years old, in some cases, are a characteristic feature in the 

 landscape. 



Two of the large plantations were visited, and an opportunity was 

 thus given of seeing the methods in use in the cultivation of the various 

 tropical productions of Surinam — cocoa, coffee, oranges, bananas, cas- 

 sava, rubber, etc. On one estate there were extensive plantations of 

 Para rubber (Hevea b raziliensis) , and the somewhat primitive, but 

 apparently satisfactory, preparation of the sheets of merchantable rubber 

 could be seen in all stages. 



In these large plantations the canals intersecting them in various 

 directions were the principal means of communication, although along 

 the dykes were usually footpaths, which were not always, however, in 

 the best of condition — especially when the clay was slippery after one 

 of the frequently recurring showers. 



As the salinity of the water decreases in the upper reaches of the 

 rivers, the mangrove formation is gradually replaced by other trees 

 and shrubs. Several Leguminosas, especially species of Inga, are com- 

 mon, and great numbers of a big Arum (Montrichardia arborescens) , 



