22 



PLATE V. 



ISLAND OF UALAN, CAROLINE ARCHIPELAGO. 



MANGEOVES. 



December. 



Of the characteristic forms of the mangroves we met fine specimens in this island, 

 lat. 5° N. This kind of forest covers the shores of the tropics as reeds and bul- 

 rushes do the margins of our inland lakes. In this climate, wherever the shores 

 are formed by swamps, L e. principally at the mouths of rivers and rivulets, and 

 at the same time protected from the surf, this form of vegetation may be ex- 

 pected. It appears to attain its perfection and show its peculiarities most nearest to 

 the equator, but every continent (or every one of those large longitudinal sections) 

 possesses its own species to form these groves. They are composed, generally 

 speaking, of the genera Rhizophora and Bruigiera, trees of indifferent height, 

 growing upon a soil which, as a rule, is at least during high tide covered with 

 salt water, and throwing out numerous aerial roots. On the Indian coast are 

 associated with them species of Sonneratia and the stemless Nipa palm (Nipa 

 fruticans, Thunb.), which exercise a marked influence on the physiognomy. All 

 these plants exhibit a decided tendency towards gregariousness^ quite contrary to 

 the common character of the tropical forests. These groves are also, it would 

 seem, destitute of the numerous creepers seen in their immediate neighbourhood.* 

 In Ualan, and, as far as we could judge from a distance, in the larger island 

 of Funopet, it is not so much the true mangrove trees (Rhizophora and 



* Perhaps Entada scandens, Bth. ( = Mimosa scan- above high-water mark, cannot be classed with the 



dens, L.) forms the only real exception I can call to real swamp vegetation of which the author here 



mind. I have seen festoons of this creeper several treats. They belong, properly speaking, to the ve- 



hundred yards long in the mangrove swamps of getation immediately following the mangroves, 



Fiji. Guilandina Bonduc and Tephrosia piscatoria, composed of Barring tonia speciosa, Calophyllum 



though sometimes throwing their branches over inophyllum, Hibiscus tiliaceus, Thespesia popul- 



mangrove trees, if they happen to grow close to soil nea, &c. — Berthold Seemann. 



