RHOPALOCERA MALA VAX A. 285 



thread that seemed every moment in dau,t;-er of vanisliing. But to my astonished eyes the 

 whole place appeared a garden of flowers of a thousand colours, and crowded so close l)y the 

 water that the sand could scarcely he seen. I looked and looked again, and then stepped 

 down to ohserve the parterre closer ; hut as I did so these animated hlossoms sprang into the 

 air in a huge cloud, and the truth was plain that they were a countless host of thirsty 

 butterflies, collected from the forest all round to drink at this thread of liquid." * Sometimes 

 these swarms appear both suddenly and unexpectedly, as related of a species, Tcrias lisa, in 

 Bermuda. According to Mr. Jones, the butterfly was lirst observed on " 10th October, 1847, 

 on which day it suddenly appeared in great abundance, hundreds being seen in every 

 direction They all disappeared, however, in the course of a few days." f 



This brings us to the subject of migration, and here we are again indebted to Mr. Jones 

 for an excellent account of a swarm of this same species which visited the Bermudas in 

 October, 1874. " Several persons living on the north side of the main island perceived, as they 

 thought, a cloud coming over from the north-west, which drew nearer and nearer to th(> shore, 

 on reaching which it divided into two parts, one of which went eastward and the other 

 westward, gradually falling upon the land. They were not long in ascertaining that what they 

 had taken for a cloud was an immense concourse of Tcrias lisa, Boisd., which flitted about all 

 the grassy open patches and cultivated grounds in a lazy manner, as if fatigued after their long 

 voyage over the deep. Fishermen out near the reefs, some few miles to the north of the 

 island, very early that morning, stated that numbers of these insects fell upon their boats, 

 literally covering them. They did not stay long upon the island." I During Mr. Spruce's 

 sojourn in South America he witnessed large flocks of butterflies pass across the Amazons near 

 the mouth of the Xingu in November, 1849, in a direction from about N.N.W. to S.S.E., 

 evidently in the last state of fatigue, "all of common white and orange-yellow species." The 

 little wind there was blew from E. to N.E., and therefore the butterflies steered their course at 

 right angles to it. § In Ceylon Sir Emerson Teunent watched the "extraordinary sight" 

 " of flights of these delicate creatures, generally of a white or pale yellow hue, apparently miles 

 in breadth, and of such prodigious extension as to occupy hours, and even days, uninterruptedly 

 in their passage — whence coming no one knows ; whither going no one can tell." || On Sunday, 

 July 5th, 184G, an enormous flock of white butterflies arrived at Dover from the French coast. 

 It was described as being so extensive as to pass like a cloud of snow. IT The late Mr. Darwin 

 describes one such swarm which he witnessed when about ten miles from the Bay of San Bias. 

 "Vast numbers of butterflies, in bands or flocks of countless myriads, extended as far as the 

 eye could range. Even by the aid of a telescope it was not possible to see a space free from 

 butterflies. The seamen cried out 'it was snowing butterflies'"; and these again were 

 principally ricriiue, as Mr. Darwin found the most common butterfly to be a species of the 

 genus Colzas.** 



The pseudonymous 'Eha,' who has written so pleasantly of Natural Ilistory in ludui, 

 observes that " butterflies of some kinds— especially those energetic greenish-white ones of the 



'■■ ' On the Indian HiUs,' vol. ii. p. 314. t ' Naturalist in Bermuda,' p. 120. 



I ' Psyche,' Dee. 1875, No. 20, p. 121. § Jouru. Linn. Soc, Zool. vol. ix. p. 350. 



II Nat. Hist. Ceylon, p. 403. '" J- romberton, ' Zoologist,' vol. iv. p. 1442. 

 ■:■■■:■■ 'Voyage of the Beagle,' p. 158. 



March 20, 1885. '^ " 



