THE VEGETATION OF THE JUAN FERNANDEZ ISLANDS 



819 



The cH)>iaic of Masatierra compared to tlic cliuiate of Macarojiesia. 



It lies near to hand to compare the chmate of Masatierra with other insular 

 climates with winter rains in approximately the same latitude, but in order to find 

 them we have to turn to the Atlantic, where the Macaronesian islands, Cajje Verde 

 Is. excepted, should offer suitable stations. Raunkiaer {6) Has published hydro- 

 therm figures for the Azores, Madeira and Teneriffe at or very near sea-level. 

 Plotting the curves for Masatierra on these figures, we find a striking conformity 

 in the run, with the self-evident difference that Masatierra on the south hemisphere 

 presents them in inverse position. A comparison is shown in Table XIII, where 

 I have added the figures for Valparaiso. 



Table XIII. The figures have been rounded off. Months indicated by Roman figures, 

 temperatures Centigrade, precipitation in mm. 



There is considerable resemblance between Masatierra and the Azores, where, 

 however, the temperature is a little higher and the rainfall smaller, and Madeira 

 has a milder winter and a much drier summer. In the Canary islands the hottest 

 as well as the coldest month is 4° warmer than in Bahi'a Cumberland, and there 

 is a period of drought in the summer. The question now arises to what extent 

 the character of the vegetation, as expressed in the percentage of the life-form 

 classes, is the same. I shall return to this question later. 



Soils. 



The soils of Juan Fernandez have never been studied. As I am quite in- 

 competent to deal with this subject, the miscellaneous notes assembled below have 

 little scientific value. 



On the lower slopes of Masatierra and in the valley bottoms near the sea, 

 where the forest cover has disappeared, naked soil is largely exposed. The colour 

 is a yellowish to reddish brown or even brick-red, but without the brilliancy of 

 the soils of the Tropical volcanic islands of the Pacific. A water-colour sketch 

 in the popular account of the expedition (Till Robinsonon och varldens ande, 

 191 8) gives an idea of the colouring in Bahia Cumberland. The basal region of 

 Masafuera consists of darker and harder lava and the soil is less colourful. The 

 barren slopes of Masatierra, especially in the central, deeply dissected part, are 



