DOWN THE AMAZONS. 371 



of the tropics may produce upon laminated clays of recent 

 origin the same effect as plutonic agencies have produced 

 upon the ancient clays,- -that is, it may change them into 

 metamorphic slates. As I approached the serra, I was 

 again reminded how, under the most dissimilar circum- 

 stances, similar features recur everywhere in nature. I 

 came suddenly upon a little creek, bordered with the usual 

 vegetation of such shallow watercourses, and on its brink 

 stood a sand-piper, which flew away at my approach, utter- 

 ing its peculiar cry, so like what we hear at home that, 

 had I not seen him, I should have recognized him by his 

 voice. After an hour's walk under the scorching sun, I 

 was glad to find myself at the hamlet of Erere, near the 

 foot of the serra, where I rejoined my companions. This 

 is almost the only occasion in all my Amazonian journey 

 when I have passed a day in the pure enjoyment of nature, 

 without the labor of collecting, which in this hot climate, 

 where specimens require such immediate and constant at- 

 tention, is very great. I learned how rich a single day may 

 be in this wonderful tropical world, if one's eyes are only 

 open to the wealth of animal and vegetable life. Indeed, a 

 few hours so spent in the field, in simply watching animals 

 and plants, teaches more of the distribution of life than a 

 month of closet study ; for under such circumstances all 

 things are seen in their true relations. Unhappily, it is not 

 easy to present the picture as a whole ; for all our written de- 

 scriptions are more or less dependent on nomenclature, and 

 the local names are hardly known out of the districts where 

 they belong, while systematic names are familiar to few." 



January oOtJi. On board the " Ibicuhy." Yesterday 

 we parted from our kind hosts, and bade good by to Monte 

 Aldgre. I shall long retain a picture, half pleasant, half sad, 



