1914.] 187 



period and extent of this later distribution we owe largely to 

 Professor Semper,* who states that the butterfly was first seen in 1863 

 by Captain Rachan, one of numerous collectors of the Museum 

 Godeffroy on the islands of the Tonga or Friendly group, again nearly 

 2,000 miles from Ponape. The first specimen actually obtained was 

 secured in 1866 on Niuafau, one of the islands of this group, and in 

 the same year larvae were discovered on Asclepias curassavica, a plant 

 now spread quite as far as the Anosia. We now begin to be able to 

 record in part the rapidity of its spread ; for it was first seen in 

 Tutuilla, one of the islands of the neighbouring Samoan group, in 

 1867, but upon Upolu and Savaii, islands of the same Samoan group, 

 distant at the nearest some fifty miles, not until 1869. Yet in Upolu 

 it became one of the commonest butterflies in 1870. It was not until 

 1868 that it was discovered at Tongabalu (sic), one of the southern 

 of the Tonga Islands, but in the same year it was seen in the open 

 sea five hundred nautical miles to the south-east. In 1869 it had 

 appeared at Eoratonga, one of the Hervey Islands, five hundred 

 miles or more away. In 1870 to 1872 it was found on Huahine 

 and Tahiti, of the Society Islands, again five hundred miles or more 

 distant. So far the account of Professor Semper. But Mr. James 

 J. Walker, who sailed in the South Seas in 1883 and found 

 Anosia nearly everywhere one of the commonest butterflies, states 

 that he was informed at the Marquesas Islands, which lie to the 

 north-east of the Society Islands, again at a distance of some five 

 hundred miles, by a Roman Catholic missionary residing there forty 

 years, that he distinctly remembered seeing the first specimen there 

 about 1860 ; it should be noted that the Marquesas Islands are nearly 

 as distant in a south-easterly direction from the Hawaiian Islands as 

 the Carolines are to the south-west. Mr. Walker also found the 

 butterfly on the Hervey and Society Islands, and at Oparo, one of the 

 Andaman (sic !) group, in 28° south latitude, though it had not then 

 reached Pitcairn Island, which lies much farther east and somewhat 

 farther north. These statistics indicate its movements from the Caro- 

 line Islands in an easterly and south-easterly direction, but it has also 

 left its mark by the way in a southward extension from this route of 



travel It reached Lord Howe's Islands in 1870, Clarence River 



on the opposite coast of Australia in 1871, Melbourne in 1872, and 

 has now extended to Celebes, and, according to Kirby, to Java. 



*G. Semper on the appearance of DanaU archippu* in the South Sea Islands, 

 Australia and Celebes : Journ. Mua. Godeffroy, II, pp. 117-119 (1873). 



