210 THE COLOUBS OF ANIMALS 



Similar features in Mollusca 



Semper ' has shown that certain freely exposed 

 and active snails in the Philippines (Helicarion) have 

 the same power of readily parting with their tails, 

 and this is also true of a snail in the West Indies 

 (Stenopus). The tail, or rather hinder part of the foot, 

 which the animal sheds when it is seized and after- 

 wards renews, is more conspicuous than the rest of the 

 body. Semper found that the tails had been shed in 

 about ten per cent, of the individuals of a species 

 (Helicarion gutta) very common in the north-east of 

 Luzon. 



Recognition Markings 



A special kind of marking is often of great value 

 in attracting the attention of individuals of the same 

 species, instead of attracting the attention of enemies. 

 From its obvious relation to the latter form of marking 

 it is best included under the division of Warning 

 Colours. Mr. A. E. Wallace has directed attention 

 to the importance of Eecognition Markings, and an 

 account of them will be found in his recently published 



seems to be not uncommon in certain localities in this country. The 

 tail becomes cream-coloured at the end of summer, but resumes its 

 ordinary appearance at the beginning of winter. Smaller differences 

 appear to be general, the summer fur on the tail being coarser and 

 more uniformly red than the winter fur. Bell's British Quadrupeds, 

 2nd edition, p. 279. 



1 Semper : Animal Life, International Scientific Series, pp. 395 



