Chap. XX.] EXCURSION TO THE MOUNTAINS. 449 



could not but be most advantageous that the plant should be 

 introduced into many other tropical countries. On our way 

 up the valley we had passed numerous natives, going down to 

 Papeete with loads of " Fei." 



Rats live in the mountains, and climb up and devour the 

 ripe Bananas, and the groves of the trees are traversed in all 

 directions by the tracks of wild pigs, which likewise feed on 

 the fruit. It is strange that the pig should run wild and thrive, 

 under such widely different conditions as it does, and should 

 be able to exist equally well on wild Plantains in the warm 

 Tahiti, and on Penguins and Petrels in the chilly Crozets. In 

 this power of adaptation it approaches man. 



It had been raining heavily during our walk, and was still 

 pouring when we halted, and we were all wet through. The 

 guides soon built a small waterproof hut, with sticks and the 

 huge wild Banana leaves. Then they put up another small 

 roof of leaves, and finding dry dead Banana leaves under the 

 shelter of the freshly fallen ones, soon lighted a fire under the 

 roof, and we dried our clothes in the smoke before nightfall, in 

 the midst of the heavy rain. The Banana leaves afforded 

 further waterproof covers for our clothes and for my botanical 

 drying paper. 



We had brought no blankets with us, because I wished to 

 make the utmost attempt to scale the mountains as far as 

 possible, and had therefore reduced the baggage to a minimum. 

 I had not expected that we should suffer from cold as we did. 

 The thermometer showed, at about half an hour before sunset, 

 75° F. ; about an hour later 68°'5 ; at midnight 63°'o ; at day- 

 break 6o°'5, and in about half an hour after daybreak it rose 

 to 61 '5°. The main stream of the valley running past the 

 huts had a temperature at daybreak of 65°'o, having retained 

 throughout the night the heat of the former day, which the air 

 had so rapidly lost. The effect of the stream on the climate 

 here is thus just the opposite of that of the streams of such 

 an island as Tristan da Cunha.* 



From this camp, the way led over several steep minor ridges 

 in the head of the valley, and then up to an elevation of 3,000 

 feet, which was reached on one of the extremely narrow ridges, 

 characteristic of Tahiti, situate just to the west of the " Diadem." 

 From the ridge, a descent was made into the Punaru Valley 

 by the aid of ropes fastened to the trees. The precipitous 

 side of the valley which we thus descended was covered at 

 this elevation, from about 3,000 to 2,000 feet altitude, with a 

 dense vegetation, composed almost entirely of ferns. A Tree 

 Fern {Alsophiia tahitiensis) formed a sort of forest, to the exclu- 

 * See page 96. 



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