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fine specimen growing in a fish pond, at the Kahhi Farm, near 

 Honoluki, belonging to the Alexander Young Estate. This tree 

 was planted by Mr. Allan Herbert, many years ago, and is now 

 in flourishing condition. So far as is known to the writer, it is 

 the only tree on the Island of Oahu. Under the direction of Mr. 

 George Cooke there have been extensive plantings of mangrove 

 along the shores of the Island of Molokai. The trees were plant- 

 ed as a source of floral honey, as Molokai is a noted honey- 

 producing region. The trees are spreading and seeding and rapid- 

 ly becoming thoroughly naturalized. The mangrove is not men- 

 tioned by Hillebrand, or by any other of the many botanists who 

 have visited and written of the native and naturalized plant life 

 of Hawaii. The tree specified is not only in vigorous growth, but 

 has produced many seedlings wdiich have evidently become thor- 

 oughly naturalized. The evidence strikingly corroborates the 

 writer's previous conviction as to the Hawaiian possibilities of 

 the mangrove. 



The family Rhizophoracea?, of which the mangrove is char- 

 acteristic, comprises 15 genera and about 50 species. Prominent 

 among the genera are: Wcihea, 12 spp.. Old World tropics; 

 Ccriops, 2 spp.. Old World tropics ; Pruguiera, 5 spp. tropical Asia 

 and East Africa; Anisophyllca, 5 spp.. Old World tropics; Pogo, 

 1 spp., Africa. RJiizophora has 3 species, mangle, of tropical 

 America and West Africa ; mucronata and conjugata, of tropical 

 Asia and East Africa. These three are widely distributed on the 

 shores of tidal marshes and estuaries. The generic name is from 

 the Greek, root-bearing, and was used by early writers to desig- 

 nite various climbing plants with aerial roots. 



The genus is almost unique in the plant world because the seeds 

 have no true resting period, that is, they germinate at once on 

 the plant. The radicle may reach a length of 3 feet, although 

 usually less ; it is club-shaped and heaviest at the apex, so that 

 when the seedling finally falls from the tree, it sticks vertically 

 in the mud, wath the radicle down, ready to grow. This is one 

 of the best examples of vivipary, as the embryo continues in a 

 state of uninterrupted development from the outset. This is 

 essentially seedlessness, from the physiological standpoint, and 

 germination, in the usual sense, does not take place. This habit 

 is of obvious usefulness, facilitating both the wide dispersal and 

 abundant reproduction of these plants, as is testified by the exten- 

 sive coastal mangrove swamps throughout the tropics. This ex- 

 traordinary combination of structural and ecologic characters — 

 vivipary, aerial roots, ability to grow in salt water, rapid lateral 

 growth, and freedom from fungus and insect pests — has given 

 to the mangroves a tremendous advantage in the invasion of 

 tropical coasts. 



The name mangrove is derived, by corruption, from the orig- 

 inal Malayan name mangi-inangi. The American species, R. 

 mangle L., is called Red Mangrove, referring to the color of the 

 inner bark. There are various trees in other regions that are 



