302 The Andes and the A:viazon. 



boldt) " that it is so rare to find papers in tropical America 

 older than fifty or sixty years." 



Dragon-flies are conspicuous specimens of insect life on 

 the Amazon. The largest and most brilliant kinds are 

 found by the shady brooks and creeks in the recesses of the 

 forest, some of them with green or crimson bodies seven 

 inches long, and their elegant lace-like wings tipped with 

 white or yellow. Still more noticeable are the butterflies. 

 There is a vast number of genera and species, and great 

 beauty of dress, unequaled in the temperate zone. Some 

 idea of the diversity is conveyed by the fact mentioned 

 by Mr. Bates that about 700 species are found within an 

 hour's walk of Para, and 550 at Ega; while the total num- 

 ber found in the British Islands does not exceed 6Q, and 

 the whole of Europe supports only 390. After a shower 

 in the diy season the butterflies appear in fluttering clouds 

 (for they live in societies), white, yellow, red, green, pur- 

 ple, black, and blue, many of them bordered ^vith metallic 

 lines and spots of a silvery or golden lustre. The sulphur- 

 yellow and orange-colored kinds predominate. A colossal 

 morpho, seven and a half inches in expanse, and visible a 

 quarter of a mile off, frequents the shady glades ; splendid 

 swallow-tailed papilios, green, rose, or velvety-black, are 

 seen only in the thickets ; while the Hetaira esmeralda, 

 with transparent wings, having one spot of a violet hue, as 

 it flies over the dead leaves in the dense forest looks " Hke 

 a wandering petal of a flower." Very abundant is the He- 

 liconius, which plays such an important figure, by its varia- 

 tions, in Wallace's theory of the origin of species. On the 

 Maraiion we found Callidryas eubide, a yellow butterfly 

 common in Florida. The most brilliant butterflies are 

 found on the Middle Amazon, out of reach of the strong 

 trade winds. The males far outnumber the other sex, are 

 more richly colored, and generally lead a sunshiny life. 



