of Dcmais xLrcldppus. 9.) 



Europe and the Azores, aud then westward to the South 

 Sea Isles and Australia. 



That the winds alone are a great agency of dispersal 

 with the Lejridoptera cannot be doubted with the number 

 of authentic records we have of butterflies and moths being 

 found far at sea and great distances from the nearest land ;* 

 and it will readily be understood that butterflies of high 

 and strong flight, especially when at certain seasons they 

 become gregarious, must have a greater chance of being 

 borne on the wings of a strong wind or carried away by a 

 sudden gale than those insects whose flight is low, or whose 

 habits are more solitary and secluded. JS[ow we know that 

 J). Archippus has a powerful flight, often sailing with 

 wings expanded high in the air, and was frequently seen 

 by E. Doubleday crossing the Ohio and Mississippi, 

 where those streams were more than a mile in breadth,! 

 and Mr. Gosse, describing the insect in Jamaica as flying 

 low about the logwood hedges, says, "but there are no 

 trees near, or it would probably have towered above 

 them. "I We also learn from Mr. liiley that the butterfly 

 appears in large bevies or flocks almost evei^y year in some 

 j)art or other of the west. In September, 1868, accounts 

 were received of their sudden appearance in different parts 

 of the city of Madison, Wisconsin, and at Manteno, Ills.; 

 whilst on the 19th of that month at St. Joseph, Mo., 

 millions of them Avere seen filling the air to the height of 

 three or four hundred feet, for several hours flying from 

 north to south. In the spring of 1870 a remarkable 

 swarm was seen at Manhattan about the middle of April, 

 and which, as reported by a resident of that place, came 

 rapidly with a strong Avind from the N.W., and filled the 

 atmosphei'e all round for more than an hour, sometimes so 

 as to eclipse the light. Mr. Kiley further remarks, " this 

 assembling in large flocks at a consideraljle height would 

 always be a source of danger to them Avhen overtaken by 

 a gale of wind, when there would be a great probability of 

 their being carried out to sea."§ 



•JD. Archippus has likewise a longevity in the imago 

 condition, Avhich Avould also assist its survival on a long and 

 forced migration, Mr. INlitchell having kept a female alive 

 for forty days. She was kept in an empty Avardian case, 



• Sec :\Iiillcr, Trans. Ent. Soc. 1871. 



t Gen. Dinrn. Lcp. p. 'JO. 



t Ann. & Mao-. Nat. Hist., Scr. 2, vol. ii. p. 114. 



§ Thinl Ami. K^p of Ii.. ..f Mi>s. p 151. 



