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have claimed, and have created, a Uterature of their own. 

 Such hteraturc must be especially interesting to us, because, 

 in the case of many of the theories advanced, there is a 

 strong tendency to throw the burden of proof upon facts and 

 deductions connected with entomological science. Already 

 we have to welcome a new publication devoted entirely to 

 such subjects. The ' Entomologist's Kecord and Journal of 

 Variation,' edited by Mr. Tutt, has appeared within the 

 year ; and Mr. Poulton has lately added another valuable 

 contribution to the elucidation of Darwinian problems. His 

 book on the meaning and use of the colours of animals, 

 — one of the volumes of the International Scientific Series, — 

 has special reference to Entomology. However guarded we 

 may be in the degree of acceptance accorded to the theories 

 he seeks to advance, we cannot but be greatly interested in 

 his admirable summary of the work already done, and in his 

 excellent attempt to corroborate, by new observations and 

 experiments, many of the conclusions already more or less 

 generally accepted. 



With regard to the uses of colour in insects for protective, 

 aggressive, or attractive purposes, so much has been said 

 and written that it seems difficult to add any new suggestion ; 

 but there is one point to which only a slight allusion is 

 made in Mr. Poulton's book, and which I do not remember 

 to have seen insisted upon elsewhere, — viz. the value of 

 bright colours, temporarily displayed, as a means of increasing 

 the degree of security derived from protective tints. My 

 attention was lately drawn to a passage in Herbert Spencer's 

 ' Essay on the Morals of Trade.' He writes : — " As when 

 tasting different foods or wines the palate is disabled l)y 

 something strongly flavoured from appreciating the more 

 delicate flavour of another thing afterwards taken, so with 

 the other organs of sense, a temporary disability follows an 

 excessive stimulation. This holds not only with the eyes in 

 judging of colours, but also with the fingers in judging of 

 'textures." 



Here, I think, we have an explanation of the principle on 

 which protection is undoubtedly afforded to certain insects 

 by the possession of bright colouring on such parts of their 



