2lO MR. C. F. U. SWYJSINEETON ON THE 



though I have collected largely at the fruits aud flowers that bring butterflies 

 together as the Eucalyptus saliqna flowers bring the bees. 



Therefore, considered absolutely, attacks on butterflies, whenever and 

 wherever they are thus outnumbered, are unlikely to be as numerous as those 

 on the insects that outnumber them. Even relatively, however, butterflies 

 are likely to sufler somewhat less than more abundant insects — that is, i£ my 

 own observations and those of, I believe, at least one American observer (Mr. 

 H. C. Bryant), to the effect that birds tend to concentrate their attention 

 somewhat specially on what (of an acceptable nature) is at the time most 

 readily obtainable in quantity, be correct. 



These factors, with certain others not worth going into again here as I 

 have dealt with them so recently, probably account for the otherwise puzzling- 

 fact that we do actually see fewer attacks on butterflies than on insects of 

 certain other orders. But, at (^hirinda — and I have at present no reason to 

 suppose that the locality may be exceptional in this respect — I have obtained 

 evidence that even if they should enjoy a certain amount of relative immunity 

 under the circumstances I have suggested, butterflies are probably neverthe- 

 less very greatly persecuted, even at times by those birds that specialize 

 primarily in other directions ; and I find it interesting to contrast my results 

 obtained during two different periods. 



In eleven years, during which I paid no very special attention to the .subject, 

 I witnessed only about twenty attacks by wild birds on butterflies. In four 

 years, during small portions oE which I did pay special attention to it, I 

 obtained records of over 800 such attacks. Nearly all these were witnessed 

 by myself, the majority of them within a single month, during which I made a 

 point of working at the subject amongst the wild birds of the forest outskirts 

 for an hour or two each day. The method was mainly (not solely) experimental, 

 but in many of my experiments thoroughly vigorous, unmaimed and strongl}'- 

 flying butterflies were freely used, and even these drew numerous attacks. 

 Again, during the first period mentioned, I examined, non-microscopically, 

 more than 1000 stomachs of insectivorous birds, and in only five found 

 butterfly remains. I later found, by the close examination of pellets the raw 

 material of which was known to me, that butterflies, including their wings, 

 tend to be broken up so finely in a bird's stomach that their presence is often 

 only to be recognized by the use of a lens that will readily show the scales, 

 etc., and their absence only to be established as the result of a completely 

 exhaustive examination of the whole of the finest debris, which in some cases 

 may take very many hours. This led me to a decision to re-examine the 

 stomach-contents I had collected, and although up to the present, through 

 lack of time, my re-examination has not proceeded far, the initial indications 

 are that the proportion of stomachs with Lepidopterous remains will be higher 

 than at first. Other lines of investigation (testing of newly captive and wild 

 birds for previous knowledge, examination of excreta picked up at random 



