The Origin of the Markings of Caterpillars. 345 



morning twilight, or at night, and of concealing 

 themselves by day, it must be advantageous for 

 them to have the surface of their large bodies not 

 only divided by white stripes, but also interrupted 

 in yet another manner. How could this be better 

 effected than by two .spots which, in colour and 

 position, represent the grouping of the red berries 

 on the branches ? When feeding, the insect 

 always rests with the hind segments on a branch, 

 the front segments only being more or less raised 

 and held parallel to the leaves ; the red spots thus 

 always appear on the stem, where the berries are 

 likewise situated. It might indeed be almost 

 supposed that the small progress which the 

 formation of secondary ring-spots on the other 

 segments has made up to the present time, is 

 explicable by the fact that such berry-like spots 

 on other portions of the caterpillar would be rather 

 injurious than useful. 



It may, however, be asked how an imitation of 

 red berries, which are eaten by birds just as much 

 as other berries, can be advantageous to a cater- 

 pillar, since by this means it would rather attract 

 the attention of its enemies ? 



Two answers can be given to this. In the 

 first place, the berries are so numerous on every 

 plant that there is but a very small chance of the 

 smaller and less conspicuous berry-spots catching 

 the eye of a bird before the true berries ; and, 

 secondly, the latter, although beginning to turn 



