I 



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the periods when the fine Vernonia podocoma bushes that 

 line portions of the Chirinda Forest outskirts are attracting 

 numbers of butterflies they become greatly frequented by 

 certain birds also, and, watching from a little distance, one 

 often sees a sudden sharp movement at the back of a flower- 

 head or the quick dash of a bird over the top of a panicle on 

 which butterflies and Hymenoptera may be feeding together. 

 But it is seldom possible to see which prey is taken. Yet 

 each time I have searched the foot of the bushes I have found 

 freshly broken butterfly-wings. A case in which a green 

 bulbul, that I would certainly not have seen had I not been 

 looking at that very point, appeared momentarily (from 

 behind) between outer leaves on which butterflies were bask- 

 ing, seized one of them and as quietly withdrew, is highly 

 instructive. 



This all applies to the small closely-searching birds that 

 form the very great bulk of our insectivorous bird-population. 

 There are other birds that do not attack (necessarily) under 

 cover, such as drongos, paradise and spotted flycatchers and 

 bee- eaters, but tackle the butterfly they are hungry enough 

 for on the wing, and if necessary pursue him. We tend to 

 see rather more numerous attacks on the part of such birds 

 as these, and one reason why we do not see still more is prob- 

 ably to be found in the fact that the butterfly, if not captured 

 right away, very commonly at once goes to ground and is no 

 longer available. As Prof. Kathariner (observation stated 

 by Marshall, ihid., p. 350) wrote of an attack by a flock of 

 bee-eaters on Thais cerisyi that was " flying in great numbers " : 

 " In the shortest space of time there was not a butterfly to 

 be seen. Those that were not eaten had hidden under the 

 herbage." I am able to confirm this observation as to the 

 general result on the pleasanter butterflies of the arrival of 

 a flock of bee-eaters. Naturally unless one is present at that 

 arrival one sees few or no attacks on such butterflies. I 

 know nothing of the behaviour of migrating butterflies in 

 relation to these birds. 



Migratory locusts do not go to ground in this wholesale 

 manner ; neither are Danainae and Acraeinae (as I have seen 

 in relation to bee-eaters) as easily frightened as the higher- 



