in ANIMAL LIFE IN THE TROPICAL FORESTS 275 



machia trochilus and colubris) literally swarmed on the sands, 

 their glittering wings lying wide open on the flat surface." 1 



When we consider that only sixty-four species of butter- 

 flies have been found in Britain and about 150 in Germany, 

 many of which are very rare and local, so that these numbers 

 are the result of the work of hundreds of collectors for a long 

 series of years, we see at once the immense wealth of the 

 equatorial zone in this form of life. 



Peculiar Habits of Tropical Butterflies 



The habits of the butterflies of the tropics offer many curious 

 points rarely or never observed among those of the temperate 

 zone. The majority, as with us, are truly diurnal, but there 

 are some Eastern Morphidse and the entire American family 

 Brassolidse, which are crecuspular, coming out after sunset 

 and flitting about the roads till it is nearly dark. Others, 

 though flying in the daytime, are only found in the gloomiest 

 recesses of the forest, where a constant twilight may be said 

 to prevail. The majority of the species fly at a moderate 

 height (from five to ten feet above the ground), while a few 

 usually keep higher up and are difficult to capture; but a 

 large number, especially the Satyridse, many Erycinidse, and 

 some few Nymphalidae, keep always close to the ground and 

 usually settle on or among the lowest herbage. As regards 

 the mode of flight, the extensive and almost exclusively 

 tropical families of Heliconidse and Danaidse fly very slowly, 

 with a gentle undulating or floating motion which is almost 

 peculiar to them. Many of the strong-bodied Nymphalidae 

 and Hesperidse, on the other hand, have an excessively rapid 

 flight, darting by so swiftly that the eye cannot follow them, 

 and in some cases producing a deep sound louder than that of 

 the humming-birds. 



The places they frequent, and their mode of resting, 

 are various and often remarkable. A considerable number 

 frequent damp open places, especially river -sides and the 

 margins of pools, assembling together in flocks of hundreds of 

 individuals ; but these are almost entirely composed of males, 

 the females remaining in the forests, where, towards the after- 

 noon, their partners join them. The majority of butterflies 

 1 The Naturalist on the Riwr Amazons, 2d ed., p. 331. 



