412 I\rr. G. A. K. IMarshall on 



I believe, on the contrary, tliat we are ju.stitied in the 

 opinion expressed in the last words quoted from Professor 

 Wheeler, and I have proved that we have very good 

 grounds for maintaining tliat a conspicuous insect pleasant 

 to tlie human taste is rejected with probable signs of 

 disapproval by many truly insectivorous animals. The 

 tasting of conspicuously coloured insects by entomologists 

 in general, recommended by Professor Wheeler, would I 

 believe be of very little value or more probably of no 

 value at all as evidence of the likes and dislikes of insect- 

 eating animals. Carefully conducted experiments upon 

 such animals, and still better observation of them and 

 their prey in the held, and the examination of the contents 

 of their digestive canal and the components of their fieces, 

 are the only means by which trustworthy conclusions can 

 be readied. We have to deal with a heterogeneous group 

 of animals, alike in one respect, viz. the specialization of 

 digestive apparatus and sense-organs to an insect diet. 

 It is reasonable to suppose that, whatever we may find 

 in man and other forms not markedly insectivorous, in the 

 members of this particular group there will be a specially 

 acute sensitiveness to qualitative differences amongst the 

 innumerable species from Avhich they select their food. 

 It is probable that especial keenness for certain species 

 indicates a high nutritive value, and tliat the sense-organs 

 of insectivorous animals enable them to detect and thus 

 to reject species which would have an injurious effect, or 

 at the least would be of comparatively low value as food. 

 Tliere is no reason for the belief that an equal degree of 

 specialization exists in animals which are not insectivorous. 

 Least of all is this likely to be the case in man, witli his 

 comparatively minute olfactory lubes, tlie central organ by 

 which there is appreciation of every kind of flavour as 

 well as every variety of scent. 



I have thought it desirable to argue the question at 

 some length, inasmuch as the two distinguished naturalists 

 I have quoted, as well as others, find significance in huuian 

 experience of the taste of insects. The opposite conclusion 

 has always seemed to me inevitable from the considerations 

 set forth above ; but if any doubt remains it must be 

 dispelled by reading the following account of Mr. Marshall's 

 experiments upon himself, and comparing it with those 

 which he conducted upon insect-eating animals of many 

 kinds. It is interesting that he should detect biiterness, 



