Mimicry and Warning Colours in Grasshoppers. 125 



travelling, move so slowly that the laziest snail 

 might easily overtake and pass one of their bands, 

 and even disappear beyond their limited horizon in 

 a very short time. 



They often select an exposed weed to feed on, 

 clustering together on its summit above the sur- 

 rounding verdure, an exceedingly conspicuous 

 object to every eye in the neighbourhood. They 

 also frequently change their feeding-ground ; at such 

 times they deliberately cross wide roads and other 

 open spaces, barren of grass, where, moving so 

 slowly that they scarcely seem to move at all, they 

 look at a distance like a piece of black velvet lying 

 on the ground. Thus in every imaginable way 

 they expose themselves and invite attack ; yet, in 

 spite of it all, I have never detected birds preying 

 on them, and I have sometimes kept one of these 

 black societies under observation near my house 

 for several days, watching them afc intervals, in 

 places where the trees overhead were the resort of 

 Icterine and tyrant birds, Guira cuckoos, and other 

 species, all great hunters after grasshoppers. A 

 young grasshopper is, moreover, a morsel that 

 seldom comes amiss to any bird, whether insect or 

 seed eater ; and, as a rule, it is extremely shy, 

 nimble, and inconspicuous. It seems clear that, 

 although the young Zoniopoda does not mimic in 

 its form any black protected insect, it nevertheless 

 owes its safety to its blackness, together with the 

 habit it possesses of exposing itself in so open and 

 bold a manner. Blackness is so common in large 

 protected insects, as, for instance, in the un- 

 palatable leaf-cutting ants, scorpions, mygale 



