VALIDITY OF SOME FORMS OF MIMICRY. 745 



find their way to India, but I can find no evidence of a reverse 

 condition of things, and one can scarcely credit that the few chance 

 stragglers which possibly find their way across the sea could keep 

 up this perfection of mimicr}^ in the south of the island. The 

 supposition that the sudden appearance of a pi'eviously unknown 

 species would produce further tasting experiments will not hold 

 good in this case, as the mimic so closely resembles its model 

 D. chrysijypus, which is on the wing all the year round. 



Ex2)erwients on Yoiing Uirds in Confinement. 



I am extremely doubtful as to any real value accruing from ex- 

 periments on caged birds, whether nestlings oi' adult. I^'fo one, I 

 imagine, believes that all buttertiies taste alike : no doubt some 

 are more tasty than others, and caged bii'ds fed upon butterflies 

 even with other insect food would no doubt learn in time to dis- 

 tinguish the difi'erent kinds ; but this procedure to my mind begs 

 the question, as it assumes that butterflies are an ordinary article 

 of food in the wild state, a proposition i-egarding which the 

 evidence here brought forward does not altogether support. The 

 case is diffei-ent with Ooleoptera, Hemiptera, Dijjtera and the 

 like, which are known to be the staple food of birds. Lloyd 

 Morgan's carefully conducted experiments leave no doubt that 

 certain species of birds, probably all, have very little instinct as to 

 what is good, and what not, and that they learn by imitation 

 and tasting experiments. My observations lead me to believe 

 that the former is very important. I briefly epitomize my own 

 conclusions. 



1. Young birds probably learn at first in a general way 

 what is their natui-al provender by what is brought to them 

 in the nest. 



2. That this is further developed when they have left the nest 

 but are too weak to accompany the parents when they are 

 foraging for food. 



3. That when they accompany the parents, as they do for a 

 longer or shorter time according to the species, they notice the 

 insects caught and attempt to capture them themselves. 



4. When they are left to shift for themselves they carry on 

 what they have learnt, and during this time they undertake 

 tasting experiments, but with the exception of the birds in group 1 , 

 those on butterflies are few in number ; first, because they have 

 rarely or never had butterflies brought to them in the nest ; 

 secondly, because they have very rarely seen their parents catching 

 them, and so neglect them ; thirdly, because they have considerable 

 difl^iculty in catching them, and the process of getting rid of the 

 wings is tedious and lengthy and the morsel flufiy, and possibly 

 not always agreeable. If these observations are confii-med by 

 further experience, they would account for the fact that attacks 

 on butterflies are less frequent than those on other insects. 



