92 NATURAL HISTORY OF OUR SHORES 



If a young and inexperienced bird once tastes one, it 

 perceives a very great nastiness within, and for the future 

 remembers the strongly marked colour, and avoids it, and 

 by that form of hereditary memory that we term " instinct " 

 it becomes natural to avoid these colours. 



It has been suggested that Nereis owes its colour to the 

 same end sign of not being edible. But this is wrong. 

 All fishes consider Nereis particularly good, and fishermen 

 prize Nereis as the best bait for inshore line fishing. They 

 call it " Red Cat-worm," or sometimes " Rag-worm," but 

 the latter term they apply indiscriminately to many other 

 forms e.g. Nereine Cirratulus, etc. etc. 



Now let us consider this coloration for a minute. It 

 will be seen, on looking at a specimen, that it is not due to 

 pigments, but that the iridescence is the division of the 

 rays of light through some prismatic arrangement of the 

 worm's cuticle, mother-of-pearllike, and the red flesh of 

 the worm seen through this light-dividing cuticle accounts 

 for the " diversicoloration." 



Nereis is a predaceous worm, and is armed with a pair 

 of sharp, hooked jaws, which are set at the sides of a pro- 

 trusible proboscis, an evertible part of the oesophagus, 

 and any little animal seized by these hooked jaws is drawn 

 within, and landed into the stomach, without the ordinary 

 swallowing process, which entails friction. 



Nereis is also rather pugnacious, and never fails to em- 

 ploy these hooked jaws on the fingers of those who intend 

 it no further harm than to thread it with a fish hook. 



Nereis lives among loose stones, where these are more 

 or less embedded in clean gravelly ground, at all ranges 

 of the tide. 



At certain seasons some members of the Nereis com- 

 munity change their form to some extent. They become 

 shorter and broader, and develop long, silky, swimming 

 bristles along the central part of their bodies, This form is 



