398 PACKARD— ORIGIN OF MARKINGS OF ORGANISMS. [Dec. 2. 



I might add a case which a few years ago fell under my observa- 

 tion when I observed in a street in Providence a small bird about 

 the size of the English sparrow — perhaps it was one — pecking away 

 at a large dragon fly {^schna grandh). The dragon fly was dis- 

 abled, could not fly. I picked it up, but the bird flew off, and was 

 not with certainty identified. 



These occurrences have led me to review the subject of the 

 Batesian and Miillerian hypotheses and to come to the conclusion 

 that the theories of these and of later advocates have in reality but 

 a slight basis of fact. The two points of interest are, first, do birds 

 to any appreciable extent, even the few species, like swallows, the 

 European bee-eater, and our kingbird, shrike and fly-catcher, 

 occasionally pursue and devour butterflies, i.e., depend much on 

 these lepidoptera as an article of diet ? It is of course admitted that 

 moths, as other insects, are often caught and eaten by insectivorous 

 birds. Secondly, is the protective or adaptive coloration of butter- 

 flies and other insects due to the action of natural selection, or are 

 the similarities of colors and of patterns of colors, so frequently 

 observed in all parts of the world, but especially in the tropics, 

 primarily due to simple physical causes, such as the physiological 

 deposition of colored pigments, and the action of light and 

 moisture? 



To this end I have with some care reviewed the original papers 

 by Bates, Mliller, Wallace, Poulton and others, but to my sur- 

 prise find that neither of these framers and advocates of the hypo- 

 theses in question have themselves ever actually witnessed a bird 

 catch and devour a butterfly. 



Evidence from cases observed in the United States. — We will first 

 review the evidence from cases observed in the United States of 

 America. The insect-eating habits of sparrows have recently been 

 described in a very interesting and satisfactory way by Mr. Sylvester 

 D. Judd in a recent bulletin issued by the Biological Survey of the 

 U. S. Department of Agriculture, entitled ''The Relation of 

 Sparrows to Agriculture." Mr. Judd has made this a specialty for 

 several years, spending a great deal of time in field work, both in 

 the Northern and Middle States, observing the habits of sparrows. 

 And yet he writes me, '' Personally, I have never even seen a bird 

 in the field give chase to a butterfly. The following birds, either 

 in captivity or in the wild state, have been known to eat butterflies : 

 the catbird, kingbird, wood pewee, purple martin, scarlet tanager, 



