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THE YOUNG NATURALIST, 



out to see if it has succeeded in establishing itself on our shores, I have 

 thought it well to give the above figure, and a few random remarks on the 

 subject. The woodcut gives a very fair idea of the insect, the black portions 

 of the figure being black, the shaded portions rich fulvous, and the few spots 

 round the margin white. It is best known as Danais arckippus, and is a 

 native of the American Continent, where it is generally distributed and com- 

 mon. It is well known for possessing strong migratory proclivities, and has 

 already accomplished the colonization of various lands far distant from its 

 native home. In America it may be found from the Hudson Bay territory 

 to the Amazon. It has spread from there, apparently within the last 20 or 

 25 years, across the entire Pacific Ocean, colonizing the various islands, and 

 even reaching New Zealand, Australia, and the islands of the Malay Archi- 

 pelago. An insect with such extraordinary powers of flight as this indicates 

 will only be stayed in its career by one thing, food. Its natural food is one or 

 other of the different species of Asclepias. The seed of one of these, A. cur- 

 vassavica, is said to be " eminently fitted for wide dispersal, being very 

 minute, and enveloped in a great quantity of light cottony down, and it is 

 quite possible that they may have, in the first instance, been carried un- 

 observed to the Sandwich Islands through the medium of commerce. Thus 

 the first great gap of 2,350 miles in extent (measured from the nearest point 

 of the American Continent), may have been bridged over by the plant." 

 But it may also be that the larva will feed on other than Asclepias. 



I often have butterflies and other insects brought me by seafaring friends, 

 some of whom take the trouble to mark the latitude and longitude where the 

 specimens were taken, or the distance from the nearest land. In the course 

 of the last ten years several examples of this handsome butterfly have been 

 so brought me, one being marked "600 miles from Cape Race, the nearest 

 land." This specimen is in good condition, being only slightly rubbed in 

 one place, probably by the fingers of the captor, unused to handling such 

 fragile creatures. Mr. Mathew has often seen it " more than 200 miles 

 from land. During a cruise between New Caledonia and the Solomon 

 Islands, they were to be seen every day often in numbers." The ocean be- 

 tween the American Continent and our own shores is constantly traversed 

 by vessels on which specimens could not only rest, but be helped with a free 

 passage to their journey's end. Butterflies also are able to alight on the sur- 

 face of the ocean and rise again (see Young Naturalist, Yol. If. page 29, 

 and the Supplement — Dale's British Butterflies — to the current Volume, 

 page 17). This much at any rate is certain, that the butterfly does cross the 

 ocean. Nor need it be wondered at that any insect so strong and powerful on 

 the wing can do so, for much feebler species have accomplished wonderfully 



