PHILIPPINE ERICACE/E. 



By Elmer D. Merrill. 



{From the Botanical Section of the Biological Laboratory, Bureau of Science, 



Manila, P. I.) 



This family is represented in the Philippines by four known genera, 

 Rhododendron, Vaccinium, Gaultheria and Diplycosia, all of wide geo- 

 graphic distribution, except the last which is confined to the Indo-Malayan 

 region. About forty species are already known from the Archipelago, 

 mostly confined to Ehododendron, 16 species, and Vaccinium, 19 species, 

 while the two remaining genera have two species each. 



Without exception our species of this family are plants of medium and 

 higher altitudes, generally occurring on exposed ridges of the higher 

 mountains and a])ove an altitude of 1,000 m, although a few species have 

 been found in Mindoro and Mindanao in veiy humid localities, at lower 

 altitudes. On many of the higher mountains the predominating species 

 in the elfinwood on the exposed ridges belong to Vaccinium and Rhodo- 

 dendron, and some species of these genera are found in the more shel- 

 tered ravines. The two species of Gaidtheria are always terrestrial as 

 well as most of Vaccinium and many of Rhododendron. The species of 

 Diplycosia may be either terrestrial, subscandent, or suberect terrestrial 

 shrubs, or under certain circumstances pseudo-parasitic. Vaccinium 

 ranges from small plants a few inches in height {V. micro phyllum) to 

 trees often 20 or 25 feet in height (F. cumingianum) , being mostly 

 terrestrial, altliough some species appear to be indifferently terrestrial or 

 epiphytic, while at least one, V. vidalii, has the strangling habit of most 

 species of Ficits of the section Urostigma. Rhododendron does not show 

 so great a range in size as does Vaccinium, the smallest one that I have 

 seen being about two feet in height, but epiphytic species are more 

 abundant than in the latter genus. 



Of the thirty-nine species below enumerated in the four genera, thirty- 

 six are confined to the Philippines, so far as can be determined at present; 

 showing a remarkably high percentage of endemism. An examination of 

 the table given below, giving the distribution of the species of Rhodo- 

 dendron and Vaccinium. of China, Formosa, and Malaya, including New 



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