236 THE ENTOMOLOGIST’S RECORD. 
Migration and Dispersal of Insects: Lepidoptera. 
By J. W. TUTT, F.E.S. 
Whatever interest may attach to what we may term the internal 
migration of Anosia archippus within the Nearctic region, much greater 
interest is felt in its movements to distant parts of the world. Its 
wandering habits have led it to seek other shores, and during the last 
half century it has practically encircled the globe. Before, however, 
dealing with this, one may note that Walker observes (Hint. Mo. May., 
xxil., p. 217) that at Monte Video the well-marked form erippus occurs 
in December, and that in 1881, at Callao, A. archippus was one of the 
commonest butterflies of the district, and was especially abundant in 
January and February, and scarcest in July, though one could make 
sure of seeing the imago on the wing almost any day throughout the 
year. Apart from the range of the southern var. erippus, the insect 
would appear to cover in America about 90° of latitude, since 
Walker records it from Bolivia and the Amazon district, and specimens 
have been captured at Moose Fort 50° 20' N. lat. and at Esquimault, 
in Vancouver Island, at about the same latitude. 
No doubt can exist that it was originally an American insect, and 
it appears to have reached the Hawanan Islands, some 2000 miles from 
its American home, about 1850, contemporaneously with the introduc- 
tion of its food-plant, the Asclepias. In 1857 it appears to have 
reached Ponapé, one of the Caroline Islands, about 2000 miles from 
the Hawaiian Islands. In 1868 it was taken in the Friendly Islands ; 
in 1867 in Tutiulla, one of the Samoan Islands, and in 1869 was 
observed in two others, Upolu and Savaii. In 1868 it was seen in 
the Pacific Ocean, 500 miles from land. In 1870 it was found in the 
Society Islands; Miskin first recorded it from Australha in 1870, when 
it appeared in Queensland ; in 1872, it was noted at Melbourne, but 
has now spread throughout all the warmer parts of the island, and has 
also been taken in Tasmania. Walker records it as haying occurred 
in thousands in the Sandwich Islands, in 1878, and notes it as being 
the commonest butterfly in the Marquesas, where it was unknown 
before 1860. In the Society Islands and the Cook and Hervey Islands 
it is common, and has even reached the remote little island of Oparo 
or Rap-a far away to the southward; it is also established in the Malay 
Archipelago. He further notes that, in 1883, during the cruise of the 
‘“‘ Kingfisher”? among the South Sea Islands, this was usually the 
first butterfly observed, and in some of the islands was exceedingly 
abundant considering how recently it had been introduced. Mathew 
says that it is found through the Samoan, Friendly and Fiji Islands, 
being especially abundant in the latter, has reached the North Island 
of New Zealand, as well as Norfolk Island, whilst in New Caledonia, 
where it became very abundant, it has practically exterminated itself 
by the destruction of the food-plant (an introduced weed) by the larve. In 
the New Hebrides, Solomon Islands, and New Guinea, it has become 
common, and Semper has recorded it for Celebes, whilst Kirby says 
that it has been taken in Java, and a specimen was captured on April 
19th, 1889, in the Straits of Malacca, between Penang and Singapore. 
So much for its westward migration. 
With regard to its spread in an easterly direction, we may first 
state that it is abundant in the West Indies and has, for some years 
