118 THE entomologist's RECORD. 



normally, it does but little damage, but in the months of October and 

 November, 1891, the insect increased far beyond its usual numbers, and 

 invaded the western and south-western regions of the Argentine Ee- 

 public. Burr states that they were so abundant in Buenos Aires in 

 1891, that they were crushed in thousands upon the railway, and the 

 lines being greased as it were by their dead bodies, the trains, in some 

 instances, were stopped. These swarms gradually spread towards the 

 Andes, and by the middle of December had entered southern Chili. 

 This Argentine species is described as having " a dull yellowish-green 

 coloured thorax without any reddish stripe." This at once dis- 

 tinguishes it from the allied sedentary Chilian species, S. canccllatum. 

 The Government immediately took the matter in hand, and the official 

 who was sent to report on the invasion found that the locusts had in- 

 vaded southern Chili in millions. He says : — " They had entered near 

 Villa Rica, about lat. 39° south, at 4000 feet above the level of the sea. 

 Immense numbers had died in the snowy pass, but the survivors had 

 devoured the poor Indians' crops of beans, potatoes, and tobacco. 

 Having rested and fed, they formed two columns, one flying north- 

 west and the other south-west. A few days afterwards some forty 

 tons of eggs, according to a rough calculation, were laid. I had reason 

 to believe that there were two or three other invasions by passes more 

 to the north." 



The report that was handed in to the Chilian Government resulted 

 in a sum of 200,000dols. being 'voted to defray the expenses of de- 

 stroying them, but the following April so many of the eggs hatched,, 

 and the larvfe at once did so much damage, that the same official was 

 appointed to exterminate them. He found them principally on ground 

 quite incapable of supporting them until they reached maturity, and, 

 by a policy of " masterly inactivity," he allowed the larva to starve 

 themselves, so that in a few weeks they had all died out. 



At the same time news of another invasion into the country 

 reached the official. On this occasion the swarm appeared near the 

 origin of the Bio-bio, and on March 2Gth he " reached a wood where 

 every tree was coated with such a layer of. winged locusts that the bark 

 was not visible. Next morning showed that, for miles around, the 

 country was carpeted with locusts innumerable." These specimens, 

 which are supposed to have been the progeny of the earlier Argentine 

 immigrants showed characters intermediate between 8. paranense (the 

 Argentine species that entered Chili) and S. canceUatiun (the sedentary 

 Chilian species). So marked was this, that the official suggests that <S', 

 paranense and S. cancellatnm are the same species. All the Bio-bio 

 swarm are reported to have died during the succeeding winter, or to 

 have been eaten by birds, whilst the larvae resulting from the eggs 

 laid by them ivere destroyed whilst small. 



In South Africa locusts have done considerable damage at irregular 

 periods. In 1896 Distant reported that on one morning in November 

 immense swarms stretched, without intermission, from Bellair to the 

 Congella Valley, and young mealie fields and vegetable patches were, 

 in many places, utterly spoiled. Part of a swarm passed over Durban, 

 but did not settle, whilst swarms were seen on the back beach, and, 

 although they were keeping pretty close to the ground, a westerly breeze 

 drove them rapidly out to sea. Numbers of dead locusts, which had 

 been washed up by the waves, were piled up in a line along the beach, 



