EXPLANATION OF FOKM AND COLOURING. 237 



D. COBACIAS GARMULUS. B. PREFERENCE EXPERIMENTS. 



Exp. 20. — May 18. The bird appeared somewhat hungry. She eagerly ate a 

 Charaxes candlope, a Charaxes cithceron, and a Gharaxes achcemenes, then twice 

 rejected, each time after tasting, a Nychitona medicsa $ , but readily ate another 

 Charaxes cithceron. 



[There seems little doubt that the Nychitona, for whatever reason, was liked 

 distinctly less than the last Charaxes, and at any rate not better than C. achceirtenes.'] 



Exp. 21. — May 20. I fed the bird to repletion by hand at the commencement of 

 this experiment. She ate readily immediately after a large number of various 

 grasshoppers etc., six Charaxes brutus natcdensis, mostly with one wing attached, 

 but refused a seventh, quite evidently through repletion. 



Ten minutes later I again offered the seventh Charaxes with one wing attached. 

 It was at once recognized and accepted with the greatest readiness, then well 

 crushed and eaten. Precis cehrene and Nei^tis goochi (each with one wing) were 

 however, refused witliout tasting, the bird being pi-obably in any case once more 

 replete. 



A few minutes later again she readily ate after the usual tasting a Precis cehrene 

 without wings, tasted and rejected two wingless JSfeptis goochi in succession (they 

 had already been tried and rejected by the Kingfisher), but for some time abso- 

 lutely refused to touch a Nychitona medusa with one wing, of which she possibly 

 retained unpleasant memories from two days before. Finally, however, she leant 

 forward, tasted it with the greatest caution, and at once withdrew without 

 removing it from the forceps. She now tasted and at once cinshed and swallowed 

 a Precis cehrene without wings, tasted and readily ate a Melanitis leda, tasted 

 carefully and rejected a wingless Belenois mesentina. On my now offering a 

 wingless Papilio echerioides S the bird leant forward to take it, but struck short 

 (accidentally), merely snapping off one of its antennae. This she at once threw 

 away with evident dislike, shaking her head repeatedly as I continued to hold the 

 butterfly to her and refusing persistently to have anything more to do with it. 



[I judged (no doubt, as usual, from the bird's growing difficulty in getting the 

 insects down) that the Charaxes were eaten up to or very nearly up to actual 

 repletion -point. Assuming, for convenience, that the former was actually the case, 

 I will provisionally place Charaxes brutus in what I will call Grade 1, It seems 

 likely from the refusal of Precis cebt-ene and Neptis goochi immediately afterwards 

 that they at any rate did not come higher than this Grade 1, and from the eating 

 of the Precis only a few minutes later that it did not come appreciably below it. 

 With Melanitis leda (stimulation ?) it was then eaten readily immediately after 

 the rejection of Neptis goochi and Nychitona medusa. This gives the order : 



1 . Charaxes brutus, Precis cehrene, and, perhaps, Melanitis leda. 



2. Neptis goochi, Nychitona medusa. 



The Belenois and Papilio were at any rate probably not preferred to the Precis 

 and the Melanitis.] 



18* 



