440 INSECTS ABROAD. 



Blattae, which hitter are excessively numerous about the fallen 

 foliage, scamper off before the rapidly moving mass in quite a 

 ridiculous manner. The smaller larvae of Lepidoptera and 

 Diptera fall an easy prey to them, as well as some of the large 

 obese species of the genus Formica. 



"The phalanx altogether, when passing over a tract of open 

 ground, occupies a space of from six to ten square yards. On 

 examining them closely, they are seen to move not altogether 

 in one uniform direction, but in variously spreading dense 

 columns, now separating a little from the general mass, now 

 re-nniting with it. The margins of the phalanx spread out at 

 times, like a cloud of skirmishers from the vast army." 



The Ecitons do not restrict themselves to the open air, but 

 penetrate into houses, where they exterminate every living 

 thing. My brother has had much experience of these visi- 

 tations, and the following passage is an extract from one of 

 his letters : — 



" You mention what I told you in relation to the Ants and 

 cockroaches. The time when I wrote to you on the subject 

 was my first experience of the Ant, but since then I have seen 

 the same game every year since I have lived in this country. 

 The performance always takes place just before the commence- 

 ment of the rainy season, at which time the Travelling Ants 

 commence their marches. "Wherever they make their appear- 

 ance, every living thing bolts (not that they are frightened, but 

 that their business engagements carry them elsewhere in a 

 hurry) as fast as the number of legs given them will permit. 



"The first sign of the approach of the Ants is a peculiar 

 rustling, which sounds like a few dead leaves in an eddy of 

 wind. Then a big cockroach, in size and colour like a large 

 date, scuttles across the floor, and about a yard behind him 

 comes one little Ant about a sixth of an inch in length. One's 

 first impression is that the cockroach is a great coward, but 

 his conduct is soon explained, for from every hole and crevice 

 on all sides of the house pour continuous streams of Ants, until 

 the whole floor is black with them. 



" Then our friend's fate is sealed. It is no avail to him that 

 he is many hundred times bigger than his enemies ; they fasten 

 on him in a body, and in a few minutes no sign of a cockroach 

 is visible. As a rule, these Ants go tlirough every part of a 



