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in the Transvaal as the " pigweed caterpillar," and in the 

 United States as the " beet army worm." The other species 

 has not yet been ascertained, but from descriptions furnished 

 It appears to be one of the " semi-looper " caterpillars. The 

 looper caterpillars do not progress by crawling in the ordinary 

 way, but by bringing the hinder part of the body up to the fore 

 part and arching the back, and then taking a grip with the 

 hinder pro-legs, extending the fore part to take a grip further 

 on. They are sometimes called " measuring worms." The 

 semi-loopers are more or less intermediate between ordinary 

 caterpillars and loopers. 



The eggs of L. exigua are laid in clumps upon the plant 

 upon which the caterpillars feed, and are partially covered over 

 with hair from the body of the parent. They hatch in about 

 four to five days, and the caterpillars feed up rapidly, changing 

 to pupa; in as little as twenty days. Pupation takes place in 

 the ground, and in the warmer portion of the year the moths 

 may emerge in from nine days. The caterpillars feed on the 

 foliage of the plants, but may also eat the stems and parts of 

 the roots. 



In ordinary years it has been found that these caterpillars 

 can be kept under sufficiently by making the " boys " collect 

 and destroy them during topping operations, but in certain 

 seasons they appear in too great numbers to be left so long, 

 and, in the absence of a supply of spray pumps, the whole 

 labour on the farm has to be devoted to collecting and destroy- 

 ing the caterpillars. It, therefore, should pay the grower to 

 keep a few pumps of the knapsack pattern on hand, in case of 

 a bad invasion of caterpillars. In the parts of the United 

 States where the " hornworms " constitute an annual tax on 

 the production of leaf, machines for distributing dry Paris 

 green and for spraying are a necessary part of the grower's out- 

 fit. Knapsack pumps may be purchased in Ehodesia for from 

 65s. upwards. 



Probably the most suitable spray is : 



Paris green, 1 Ib. 

 Fresh slaked lime, 2 Ibs. 

 Water, to 160 gallons. 



