Vascular Flora of Pagan Island, Northern Marianas 1 
F. R. Fosberg 2 
The island of Pagan is composed of two 
active volcanic mountains connected by a low 
isthmus. It is situated at about the center of 
the chain of young volcanic islands that make 
up the northern half of the Marianas at 18° 
6'N., 145°45'E. Its flora is not very well 
known, and doubtless a fair number of species 
remain to be found there. In connection with 
the preparation of reports on the geology of 
the island (Corwin, et al., ined.) and on a 
collection of fossil plants (Fosberg and Cor- 
win, 1958) it has been necessary to bring 
together as completely as feasible the records 
of vascular plants found there to date. 
Few botanical collectors have visited Pagan. 
Perhaps the first was A. Marche, who made 
general collections during a voyage to the 
Marianas in 1887 to 1889- There are a few 
specimens from Pagan in his collection which 
is at the Museum d’Histoire Naturelle in 
Paris. No comprehensive report on his plants 
has ever been published, and most of the 
specimens are only now being identified. It 
is not possible at this time to compile a com- 
plete list of his Pagan specimens, but those 
available are included here. The next visitor 
who left any botanical records was the Ger- 
man governor, G. Fritz, who made a voyage 
to the northern Marianas in 1901. He noted 
a few of the prominent plants, especially cul- 
tivated ones, and planted trees of several kinds 
on the various islands. His records, though 
not supported by specimens, are indicated in 
the following list by the symbol Fr in bold- 
faced type. 
1 Publication authorized by the Director, United 
States Geological Survey. Manuscript received Septem- 
ber 15, 1955. 
2 United States Geological Survey, Washington 25, 
D. C. 
A long period with no botanical work on 
the island followed until the early 1930’s, 
when the Japanese botanists became very ac- 
tive in Micronesia. In 1933 Prof. Ryozo 
Kanehira made a short visit to Pagan, collect- 
ing a few specimens, several of which he 
reported in 1934 and the others in 1935. Prof. 
T. Hosokawa made two short visits in July 
and August, 1934, during which 42 plants 
were gathered. In 1934 he listed his own and 
previous records from all the Marianas, listing 
the islands for each species. 
In 1949, under the auspices of the Pacific 
Vegetation Project, Mr. Donald Anderson 
spent a few days on the island and collected 
a fair number of species. A set of these will be 
deposited in the U. S. National Herbarium 
and others in the Bernice P. Bishop Museum 
and the New York Botanical Garden. In 1950, 
I was able to spend a day on the island and 
collected a number of specimens, sets of which 
will be deposited in the same herbaria. During 
a geological study of the island in the summer 
of 1954, Mr. L. D. Bonham, of the U. S. 
Geological Survey, collected 40 specimens in 
order to obtain identifications of plants men- 
tioned in his account of the vegetation (in 
Corwin et al ., in preparation). His specimens 
will be deposited in the U. S. National Her- 
barium. One sight record by G. L. Corwin is 
included. 
On the basis of these collections and rec- 
ords there are at present 168 species and 
varieties of vascular plants known from the 
island, 101 of which are probably indigenous, 
8 (at least) of aboriginal introduction, and 59 
probably of post-European introduction. In 
addition to these, 4 other species are recog- 
nized only as fossils (Fosberg and Corwin, 
1958). In the following list specimens are not 
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