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territories. For the past eight years no swarms have been reported, 

 and only a few solitary individuals have been captured in scattered 

 localities. The brown locust {Locusta pardalina) continued to be 

 highly troublesome, and its suppression was the outstanding admini- 

 strative work of the year. The experience of recent years has shown 

 that the long prevalent idea that outbreaks of this species originate 

 from the migration of parent swarms from the Kalahari desert is a 

 mistaken one. They undoubtedly come from individuals breeding 

 within long-occupied parts of the country. The indications are that 

 this locust is always present more or less over a great part of the 

 Union as separate individuals or in small clusters. In this state 

 it is quite impossible to combat it, and it frequently goes unrecognised 

 owing to its lacking in some degree the coloration and markings that 

 distinguish the swarming insect. The gradual formation of swarms 

 from these individuals has previously been described [see this Review, 

 Ser. A, vi, p. 359], and such swarms being expected in the season 

 1916-1917, a circular was issued in August naming the districts where 

 outbreaks were expected. These all become infested, and much 

 more heavily than was anticipated. A table show^s the distribution 

 of the pest and the extent of the operations against it. Roughly, 

 about 200,000 square miles were infested to a greater or less degree. 

 The poison used was the same as in the previous year [loc.cit.], and 

 the method of its free distribution and use is described. The results 

 as regards locust destruction were gratifying, as comparatively few 

 swarms seem to have escaped. The idea that has long prevailed 

 that winter rains cause rotting of the eggs has proved to be a fallacy. 

 There were two principal areas of infestation, one covering Beaufort 

 West and part of Murraysburg, the other a northern area on both 

 sides of the Orange Free State and Griqualand West border. Hatching 

 in the latter area began in mid-September, without the occurrence of 

 any spring rains, the egg development proceeding from unseasonable 

 general rains that fell in July. In the main northern area very little 

 rain fell through the spring and early summer, and the winter rains 

 not having sufficed to moisten all the eggs, the hatching was prolonged 

 into December and January. The insects of the main hatching that 

 escaped destruction became winged and began to migrate in the middle 

 of November ; in the last week of November a number of large swarms 

 left both the southern and northern areas, the general direction of 

 flight being towards Basutoland, into which several swarms pene- 

 trated. These migrating swarms could not be traced back to definite 

 localities and it was impossible to fix responsibility for their escape. 

 The majority of the hatchings in Bushmanland followed midsummer 

 rains and are supposed to have come from over-w^intering eggs that 

 failed to develop under the influence of the winter rains. Locust 

 flies [Wohlfahrtia bnmnij)alpis] were rare during the season and few 

 locust birds appeared until the locusts had been flying for several weeks. 

 In January and February, however, enormous numbers of birds, 

 chiefly white storks and locust hawks, were present in the northern 

 area and the almost entire absence of trouble from locusts later in 

 the season in this part of the Union is attributed very largely to them. 

 In other localities the wattled starling was reported, but was not very 

 abundant ; the small migratory locust bird [Glareola) was reported 

 definitely from only a few localities. On the whole, locust birds are 



