ix, c, i Merrill: Plants of Guam 35 
islands by winds, water, or migratory birds. On the other hand 
it may have been transmitted from island to island inadvertently 
by man. Now it is conceded that intercommunication between 
the different groups of islands in Polynesia in prehistoric times 
was probably rare, and maybe for the most part accidental. 
Some intercommunication, however, did exist. There was prob- 
ably little or no regular communication between Micronesia and 
Polynesia in this period, but the accidental method cannot be over- 
looked. Fishing and trading boats, more or less stocked with 
food, are frequently blown out to sea by storms, and are not 
infrequently cast up on distant islands. That by this method 
Polynesia was originally colonized admits of little doubt, and 
through such intercommunication some economic plants and 
some weeds have undoubtedly been transmitted from one group 
of islands to another. That such occurrences are comparatively 
frequent also admits of no doubt. In my first period of residence 
in the Philippines, five years, two cases occurred in which small 
native boats blown to sea in the Caroline Islands were cast up 
in the eastern coast of the Philippines, one in Luzon and one in 
Mindanao, in one case with most of the occupants surviving, 
in the other with most of them dead from thirst and starvation. 
The distance travelled by these small boats was from 860 to 
1,300 kilometers. Not a typhoon season passes in the Philip- 
pines but in which small native boats are blown out to sea, 
frequently never being heard from, at other times picked up by 
passing vessels, and at other times eventually reaching distant 
shores. This is to-day happening all over Polynesia, and such 
incidents have been frequent in the history of Polynesia for at 
least two thousand years. As a method of distribution of plants 
over comparatively short distances this must certainly seriously 
be considered. 
In connection with the weed-flora of Polynesia it is of some 
interest to consider the period that the islands of the Pacific 
have been inhabited, although this question cannot definitely be 
settled. What peoples, if any, were the predecessors of the 
Polynesians is not known. Some authorities 17 place the en- 
trance of the Polynesians into the Pacific at such a remote age 
that the event cannot even approximately be fixed, either by 
tradition or otherwise. Formander, 18 however, has traced the 
history of the Hawaiians to the fifth century, and concludes that 
the Polynesian migration from the Indian Archipelago may 
” Encycl. Brit. ed. 11, 22 (1911) 23. 
18 An Account of the Polynesian Race 1 (1878) 168. 
