IN DEFENSIVE COLORATION 315 



which positively repels its enemies or positively attracts 

 its prey, rather than one which is of no interest to either. 

 It is more convenient, therefore, to defer its considera- 

 tion until after the description of the Warning Colours 

 which form the models for Mimicry. 



II. SEMATIC COLOURS, OR WARNING AND 

 SIGNALLING (RECOGNITION) COLOURS ; 

 APOSEMATIC AND EPISEMATIC CHA- 

 RACTERS. 



The second great use of colour is to act as a warning 

 or signal {Sematic Colours), repelling enemies by the 

 indication of some unpleasant or dangerous quality 

 {Aposematic or Warning Colours), or signalling to other 

 individuals of the same species, and thus assisting them 

 to escape from danger {Episemaiic or Recognition Colours). 

 In a very interesting group of cases (Allaposematic), the 

 animal warns off its enemies by associating with itself 

 some other animal with unpleasant qualities and Warning 

 Colours. 



A. Aposematic or Warning Characters. 



The use of colour for the purpose of warning is the 

 exact opposite of the one which has been described on 

 p. 297, its object being to render the animal so conspicuous 

 to its enemies that it can be easily seen, well remembered, 

 and avoided in future. Warning Colours are associated 

 with some quality or weapon which renders the pos- 

 sessor unpleasant or dangerous, such as unpalatability, 

 an evil odour, a sting, the poison-fang, &c. The object 

 being to warn off an enemy, these colours are called 

 Aposematic. 



Good examples are to be found in the American 

 skunks {Mephitis mephilica*, Mephitis suffocans*, Conepatus 

 mapurito*, &c), which possess the power of emitting an 

 intolerable stench, and are, under ordinary conditions, 

 slow-moving, conspicuous black and white mammals. 



An element of Mimicry exists in the appearance of the 

 remarkable chrysalis of Limenitis populi * as interpreted 



