PROCESSIONARY CATKKI'II.I.ARS 145 



these caterpillars march in a singular fashion, which 

 has given them the name of processionaries, because, 

 in fact, they defile in a procession, one after the 

 other, and in the finest order. 



"One, the first come for amongst them there is 

 perfect equality starts on the way and serves as 

 head of the expedition. A second follows, without a 

 space between ; a third follows the second in the same 

 way; and always thus, as many as there are cater- 

 pillars in the nest. The procession, numbering 

 several hundreds, is now on the march. It defiles 

 in one line, sometimes straight, sometimes winding, 

 but always continuous, for each caterpillar that 

 follows touches with its head the rear end of the pre- 

 ceding caterpillar. The procession describes on the 

 ground a long and pleasing garland, which undulates 

 to the right and left with unceasing variation. 

 When several nests are near together and their pro- 

 cessions happen to meet, the spectacle attains its 

 highest interest. Then the different living garlands 

 cross each other, get entangled and disentangled, 

 knotted up and unknotted, forming the most ca- 

 pricious figures. The encounter does not lead to con- 

 fusion. All the caterpillars of the same file march 

 with a uniform and almost grave step ; not one has- 

 tens to get before the others, not one remains behind, 

 not one makes a mistake in the procession. Each one 

 keeps its rank and scrupulously regulates its march 

 by the one that precedes it. The file-leader of the 

 troop directs the evolutions. When it turns to the 

 ri'Jit, all the caterpillars <>f the same line, one after 

 the ether, turn t<> tin- ri.-lit ; when it turns to the left, 



