MR. E. SPRUCE ON INSECT-MIGEATIONS IN SOUTH AMERICA. 355 



any time or take any pains to ascertain the perfect insect of the 

 larvae which fed on my plants ; nor can the zoologist keep a specimen 

 of every plant which an animal feeds upon. When a zoologist, a 

 botanist, and a geologist, each having had the requisite previous 

 training, shall combine to explore anew the Amazon valley, they 

 will be able to connect many facts which now unavoidably remain 

 isolated, and to deduce therefrom many interesting particulars of the 

 course and actual distribution of organized beings therein. For 

 myself, I am free to confess that I too generally looked on the 

 insect world as enemies to be avoided or destroyed. Mosquitos 

 and ticks sucked my blood ; cockroaches ate and defiled my pro- 

 visions ; caterpillars mutilated the plants when growing ; and ants 

 made their nests among the dried specimens and saturated them 

 with formic acid, or even cut them up and carried them away 

 bodily. I recollect my horror at coming home and finding my 

 house invaded by an army of " Arriero" or "Sauba" ants, who had 

 fallen on a pile of dried specimens, and were cutting them up 

 most scientifically into circular disks whose radius was just equal 

 to the artist's own longest diameter. The few notes on insects 

 scattered through my journals relate, indeed, chiefly to ants — who 

 deserve to be considered the actual owners of the Amazon valley, 

 far more than either the red or the white man. In fine, when I 

 venture to ofier these imperfect jottings to the notice of zoologists, 

 I feel that I can at best be considered only an interloper in a pro- 

 vince not my own. 



Having above indicated the kinds of plants apparently most in 

 request with the larvae of the Lepidoptera, I wish now to recall 

 the attention of naturalists to certaia transits or migrations of the 

 adult insects across the Amazon, which have already been described 

 by Messrs. Edwards, "Wallace, and Bates, and perhaps by other 

 travellers. The first time I fell in with such a migration was in 

 November 1849, near the mouth of the Xingu, when I M^as tra- 

 velling up the Amazon from Para to Santarem ; and it is thus 

 sketched in my Journal : — 



" The wind dropping in the afternoon, we accompanied a party 

 of sailors from the brig, in a canoe, to what was now a muddy 

 island, but in the rainy season had been a shoal some fathoms 

 under water — we in quest of plants, and they of eggs of ducks and 

 "tuyuyus"; but after stumping about for above an hour in the hot 

 mud, which parboiled our legs and feet, we reembarked, having 

 found no plants except a Pontederia and a Cypervs, and the 



