ECOLOGY OF ISLE ROYALE. 271 



any known species. "With tlie exception of the Arctic regions and South 

 America, it is distributed over the entire extent of every continent." 

 (Scudder). This species is very abundant in Southern Europe; con- 

 tinually invades northern Europe but cannot establish itself. It s\<rarms 

 in immense numbers both in Europe and in America (Calif.). Fletcher, 

 '02, p. 56; Farnham, '95, p. 150; Scudder, '76. This species is probably 

 of North American origin. Its inability to withstand, even in the adult 

 stage, the winters of noi'thern Europe and northern North America, and 

 its powers of - flight suggests that this species, which is probably of 

 southeastern North American origin, reached the old world not only 

 by way of the north but also across the Atlantic Ocean. Specimens 

 have been taken at sea 200 miles from the Cape Verde Islands in the 

 Atlantic. 



Basilarchia arthemis Dru. Arthemis Butterfly. This, butterfly was 

 very abundant along the beaches, where they were frequently taken on 

 Conglomerate Bay (near I, 5) and where two specimens were taken 

 on July 10; five other specimens were taken along the beaches on July 

 19 (G. 29) and one on July 11 and 17 respectively (G. 47, 107) ; also 

 one specimen in the Light-house clearing (I, 7) on July 8, 10, 24, 26, 

 and two on July 17. A single specimen was taken along the path at 

 the outlet of Siskowit Lake (V, 9) on August 7 (G. 215). This was a 

 burned over area and was relatively open and especially so on the rock 

 exposures. Three specimens were taken in the clearing about the camp 

 on Siskowit Bay (Y, 3) on August 9 (G. 222). It was also abundant 

 in rock clearings near the head of Rock Harbor (near III, 3) on July 

 14 (G. 97). 



This purple black butterfly with its oblique white band is a con- 

 spictious form along the beach, on the rock openings, and in the clear- 

 ings and burnings. Scudder, '99, p. 225. 



Geographic Range. Newfoundland; Nova Scotia; Quebec; Ontario; 

 northern New England; New Hampshire; northern and western Mass.; 

 Catskill and Adirondack Mts., N. Y. ; mountains of Penn. ; southern 

 Mich. ; southern Wisconsin ; northern Indiana ; Minnesota ; Alberta ; 

 British Columbia ; Fort Simpson, Mackenzie. Of North American origin, 

 cf. Field, '04, p. 1. 



Anosia plexippus L. Milkweed Butterfly. Two dead specimens and 

 one yet alive were found upon the beach at the head of a small cove 

 south of the Light-house (I, 1) on July 6 (G. 19). On the following 

 day about a half dozen dead specimens were also found under 

 similar conditions. This drift must have been cast up several days 

 previously, as was indicated by its stage of decay. A single bright 

 •colored fresh looking specimen was taken near the head of Siskowit 

 Bay (VIII, '04) on August 13, and is in striking contrast to the faded 

 specimens preserved from the shore drift.' Scudder, '99, p. 95. 



The food plant of the caterpillar is milkweed, one species of which, 

 Asclepias incarnata L., was found along Washington River (II, '04). 



This species is not, in all probability, a permanent resident of the 

 island, as it cannot endure the winters of eastern Canada. Scudder 

 ('93, p. 52) has expressed the opinion that this species cannot survive 

 the winter north of the Gulf States and that those individuals found 

 further north reach there each year as migrants from the south, or the 



