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PACIFIC SCIENCE, VoL XV, January 1961 
limited range (4). Distinction of these patterns 
is rather arbitrary but may be sufficient to con- 
clude that most of the species belong to types 
which can hardly be said to be the regional, 
although in general the Oriental elements are 
predominant. 
It is remarkable that four endemic terrestrial 
species, one centipede and three pseudo-scor- 
pions, were discovered upon this tiny island. 
One of the latter group, Lechytia sakagamii Mo- 
rikawa, is very interesting because it belongs 
to a genus which, up to the present time, has 
been recorded only from Nearctic, Neotropical, 
and Ethiopean regions (Morikawa, 1952). 
FORMATION OF LAND BIOTA 
The land biota described above has been com- 
pared to the earlier results published by Yabe 
(1902), Yoshida (1902), Bryan (1903), and 
Tuyama (1938). The plant species reported by 
those writers and by me are given synoptically 
in Table 2. From this table and from informa- 
tion kindly given me by Mr. Matsubara, the 
commander of Japanese Marcus Garrison dur- 
ing World War II, we can trace the floristic 
change of the island during the last 50 years. 
With respect to trees and shrubs, only Cocos 
and M esserschmidia have continued to exist 
throughout half a century. This combination, 
one of the commonest edaphic climaxes on 
sandy beaches of the Pacific islands, in all prob- 
ability had been already well established when 
the island was discovered. Later, but before 1938, 
the island received Pisonia as a new member of 
its flora, and it is now a chief member of the 
vegetation. On the other hand, Morinda dis- 
appeared between 1938 and 1940, because this 
was reported by Tuyama but not by Matsubara. 
Although still surviving at the present time, 
the coconut palms received remarkable damage 
from human interference (cf. Appendix). 
When Bryan visited the island in 1903, palms 
grew densely in the central area of about 3 acres. 
According to Matsubara, there were only 30 
trees, about 4.5 m. high, when he arrived upon 
the island in 1941. Half of them were cut down 
at the end of that year. Moreover, as seen from 
the Appendix, all trees on the island were com- 
pletely damaged by repeated bombing during 
the war. The present arboreal stratum is, there- 
fore, the outcome of postwar regeneration. 
The origin of papaya now existing in the 
island is obscure. Bryan gave seeds of various 
plants, including papayas, to the Japanese in- 
habitants when he left the island. Later Tuyama 
reported this plant from the island. But no 
papaya trees were growing in 1941 according 
to Matsubara. He planted a few seeds in 1945, 
and some seedlings grew to the height of a 
child before being damaged by bombing. The 
plants now growing in the island seem to have 
been brought in by the U. S. Navy after the war. 
Of the herbs and grasses, tobacco and Por- 
tulacea are the only species reported by all 
writers, including myself. Judging from the 
small size and simple topography of the island, 
which permit one to walk around it within 2 
hours, it is hard to believe that any abundant 
plant species escaped the eyes of other col- 
lectors. 6 Therefore, the lack of accord among 
four collections suggests the unstable character 
of the herbaceous strata, with new inhabitants 
appearing and being replaced in their turn by 
other ones, under the influence of human activ- 
ities during the last 50 years. Ipomoea was first 
reported in 1938, but Matsubara wrote me that 
in 1943 it was found only in scattered patches 
on the island. The overwhelming dominance of 
this species throughout the island at the present 
time is, therefore, a postwar event. 
Previous information concerning land animals 
is scanty. The most important change may be 
the extinction of numerous sea birds which bred 
on the island. A catastrophic decrease may well 
be recognized if the report of Bryan ( 1903) is 
compared with that of Kuroda (1953). 
With respect to other land species, Yoshida 
(1902) briefly described a skink, gecko, "flies,” 
"red moths,” and "small flies.” Bryan also re- 
ported a skink ( Ablepharus boutonii ) and a 
gecko {Perochirus articulatus) . Therefore, both 
have been constant inhabitants during 50 years, 
although their scientific names have been 
changed since Yoshida s visit. Among three 
land crabs mentioned by him — Grapsus grap- 
6 Actually, except for Bryophyllum, all of the plant 
species collected by me were discovered on the first 
day of our survey. 
