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These mites, unless excessively numerous upon the locusts, 

 have but little effect on their hosts. If, however, they are 

 present, as they sometimes are, by the hundreds, they worr\' 

 the host to death. It is not by their attacks on the locusts 

 themselves that these mites render us a service, as will be seen 

 from the following brief summar}' of the life-history oí Troiii- 

 hidiiint lociistanim of North America which is also ligured 

 herewith. 



'• One of the most interesting as well as one of the most 

 important of our locust enemies is what we may popularly call 

 the "Locust Mite". It forms a true link between those articulates 

 which prey on the locusts, and those which attack and destro}' 



its eggs, since it combines both traits. :;: ,;, .^ .^^ ^, ■.:.. ■.;.. :=: :;: :;: ::: :;: :;: :;: 



In the mature form it lives in the ground, feeding upon all sorts 

 of animal and decomposing vegetable matter. When the locust 

 fills the ground with its eggs this mite flourishes upon the 

 abundance of food which these afford, sometimes teeming to 

 such an extent as to give the ground a scarlet hue. 



" In spring, the female lays between 300 and 400 minute 

 spherical orange-red eggs in the ground. The}^ are usually from 

 one to two inches beneath the surface and in a slightly 

 agglutinated mass, Avliich, however, easily becomes scattered 

 upon disturbance of the soil. From these eggs, in due time, 

 there hatch little orange mites which difter from the parent in 



having but six legs. .-, .-, .-, .,i._ .■., ..;., .j.., :¡: :i: :¡: :;: :;: :;: :;: :¡: 



" Active when they first hatch and impelled by instinct, these 

 little six-legged specks crawl upon the locusts and fasten to 

 them, mostly at the base of the wings or along their principal 

 veins, just as a tick fastens to a dog or sheep, or to man. Thus 

 attached to their victim, the}^ suck its juices and swell until the 

 legs become invisible. 



It is in this condition that they are most often noticed, pre- 

 senting to the ordinary observer the appearance of a bright red 

 oblong-ovoid bod\' growing from the wing. They are so firmly 

 attached b}^ the mouth, so immovable, and with the legs so short 

 and hidden that persons unfamiliar with their true nature might 

 easily mistake them for some natural growth or excrescence. 



" In due time, these swollen bodies let go their hold and drop 

 to the ground, where, clumsily and with difficulty, they crawl 

 under the first shelter afforded by some bit of loose earth or a 

 stone. Here they remain quiet for two or three weeks gradual- 

 ly swelling and changing in form. During this change the 



