318 MR. SPRUCE'S EXPEDITION— Chap. XIX. 



arborescent vegetation, and is crowned by a small breadth of 

 grassy paramo. The waters of the Chasuan nm over a black 

 or dull blue, shining, and very compact trachyte, over which, 

 in the bottom of the valleys at Limon, there is a fine-grained 

 ferruginous sandstone of a deep brown colour, in thick strata. 

 The soil is a deep loamy alluvial deposit. The ridges on 

 which the " red-bark " trees grow all deviate a little from an 

 easterly and westerly direction, and the chinchonae are far more 

 abundant on the northern than on the southern slopes. The 

 northern and eastern sides of the trees, too, had borne most 

 fruit, and scarcely a capsule ripened on their southern and 

 western sides. This is explained by the trees receiving most 

 sun from the east and north, the mornings being generally 

 clear and sunny m the summer, whilst the afternoons are 

 foggy, and the sun's declination is northerly. Mr. Spruce 

 also observed that the trees standing in open ground were 

 far healthier and more luxuriant than those growing in the 

 forest, where they are hemmed in and partially shaded by 

 other trees ; and he concludes, from this chcumstance, that, 

 though the " red-bark " tree may need shade whilst young 

 and tender, it really requires (like most trees) plenty of air, 

 light, and room wherein to develop its proportions. 



The lowest site of the " red-bark " tree at Limon is at an 

 elevation of 2450 feet above the sea, and its highest limit is 

 at an elevation of about 5000 feet. The trees nearest the 

 plain are generally the largest, but those higher up have 

 much thicker bark in proportion to their diameter. 



The havoc committed by the bark-collectors on these trees 

 within the last twenty years has been very great. The 

 enthe quantity of " red bark " collected in 1859 did not reach 

 to 5000 lbs., and in 1860 no "red bark" at aU was got out, 

 so that the trade is nearly extinct. In the valleys of the 

 Chasuan and Limon Mr. Spruce saw about 200 of these trees 

 standing, but only two or three were saplings which had not 



