PHILIPPINE ERICACEAE. 
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 , V actinium, 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 Rhododendron , 16 species, and V actinium, 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 above an altitude of 1,000 m, although a few species have 
been found in Mindoro and Mindanao in very humid localities, at lower 
altitudes. On many of the higher mountains the predominating species 
in the elfin wood on the exposed ridges belong to V actinium and Rhodo- 
dendron, and some species of these genera are found in the more shel- 
tered ravines. The two species of Gaultheria 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 (T 7 . micro phyllum) to 
trees often 20 or 25 feet in height (T 7 . cumingianum) , being mostly 
terrestrial, although some species appear to be indifferently terrestrial or 
epiphytic, while at least one, T 7 . vidalii, has the strangling habit of most 
species of Ficus 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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