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food, and though the experiments were not numerous some of the results are very significant. 

 Thus the author says, ' I then gave her four T. senegalensis without wings, which she ate 

 greedily, and on being offered a Mylothris agathina, she promptly seized it, but immediately 

 jumped back so violently that she rolled head over heels. The way she shook her head 

 clearly demonstrated the distastefulness of the butterfly, and she would not let me bring 

 it anywhere near her. I then offered her a Belenois mesentina, but with the same result ; 

 she refused to touch it every time. Thinking this might be due to her experience with the 

 Mylothris, I put the Belenois aside and offered it to her ten minutes later, when it was 

 eaten with undoubted relish. An Acraea caldarena and A. axina were then refused, but 

 without being tasted, the smell being apparently quite sufficient.' This animal varied 

 considerably from time to time in its likes and dislikes, for Mr. Marshall tells us that about 

 a week after the above tests Mylothris agathina was eaten and the following day two more 

 of the same species without apparent distaste. Three days later it ate three A. axina and 

 one D. chrysippus, although a few days after this it refused both chysippus and axina ' with 

 unmistakable signs of distaste '. The results are somewhat contradictory, though the animal 

 quite evidently disliked chrysippus and axina after previously eating them. The next 

 experiments described were with a monkey {Cercopithectis pygerythrus). This animal ate 

 with great caution, a Precis sesamus, and afterwards readily devoured P. pelasgis, sesamus, 

 B. acheloia, and two P. antilope. It then took Acraea halali and put it into its mouth, but 

 quickly taking it out again looked at it ' with the utmost surprise for some seconds and then 

 threw it away. After this the monkey would have nothing to do with an A. caldarena. 



Mr. Marshall next describes experiments made with captive baboons. These animals 

 being capable of considerable facial expression, it would naturally be expected that interesting 

 results would be obtained, and such indeed proved to be the case. Insects other than 

 Lepidoptera were offered, as was the case in some of the previous experiments, and striking 

 proof of the theory of warning colours was obtained. The following tests were made with 

 butterflies. A young baboon ate Belenois severina and B. mesentina with evident relish, 

 also Colias electra and B. ilithya. It tasted and rejected A. caldarena and D. chrysippus, 

 and rejected at sight several A. axina and A. halali. Two D. chrysippus and one A. anemosa 

 were refused at sight, Neptis agatha was tasted and neglected, whilst B. severina and Teracolus 

 achine were eaten. A very significant result must here be given in the author's own words. 

 ' A Mylothris agathina was taken with some doubt, the head and thorax were eaten, and 

 a small part of the abdomen, the rest being thrown away ; it was clearly not much appre- 

 ciated. A D. chrysippus was tasted and refused. Then an Acraea anemosa was offered with 

 underside exposed to show the bright red and black markings ; it was tasted and refused. 

 A Precis sesamus (wet season form) was then offered in precisely the same manner ; the baboon 

 took it, held it in her hand for a few moments, and then let it fly away without attempting to 

 smell or taste it. I then cut the wings off another specimen of the same insect, and this 

 was promptly eaten without any signs of distaste.' The significance of this passage cannot be 

 overlooked. The baboon, having found anemosa distasteful, clearly associated its experience 

 with the colour of the insect, and thus the Precis, though only bearing a very rough resem- 

 blance was allowed to escape, in spite of its edibility, which was immediately afterwards 

 proved. No more convincing demonstration of the working of the principle of Batesian 

 mimicry could well be conceived. 



Further experiments with other insects then followed, the most remarkable result being 

 the evident relish with which the baboons ate certain large and evil-smelling bugs, showing the 

 unreliability of human senses in regard to insect flavours. An attempt was made to estimate 



