192 BUTTERFLIES AT NIGHT 



men out that morning stated that their boats were 

 literally covered with these butterflies. Other 

 instances are recorded by Caldcleugh and Corne- 

 lius. I have elsewhere recorded ^ the tendency of 

 the Monarch (Anosia j)lexippus) to swarm along 

 tlie water edge as if preparing for a great flight, 

 and also the fact that this butterfly must have 

 flown vast distances over the Pacific Ocean to have 

 tenanted the scattered islands where it is now 

 found. Also that it was seen by one naturalist 

 in the south Pacific five hundred miles from the 

 nearest island, and on the Atlantic Ocean " hun- 

 dreds of miles from land." There is further a 

 single record of the occurrence of Pieris rapae on 

 one of the transatlantic steamers, when more than 

 a thousand miles from land. This last might 

 perhaps be accounted for on the supposition that 

 the insect had emerged from a chrysalis on board, 

 which had matured during the passage. But a 

 stiU more striking instance of the occurrence of 

 Lepidoptera far out at sea, on account of the num- 

 ber of species concerned, is given in " Science," 

 where Mr. Lucas records that while in latitude 

 25° south and a thousand miles from the nearest 

 portion of the coast of Brazil, his party 



1 See The Life of a Butterfly. New York, 1893. 



