ENEMIES OF OUTIIOl'TKKA. 



27 



the year before. These red spiders are in fad mature red mites, 

 the two sexes of which are shown in Fig'. IT. Soon a Tier appeal- 

 ing in spring, the sexes mate and the female soon deposits :>00 <n- 

 more small, globular eggs at a depth of a few inches in the soil. 

 From each of these eggs there hatches, about the time the young 

 locusts appear, a minute six-legged mite, which runs actively 

 about in search of some host to which it may attach i I self. When 

 it happens upon a young locust, it fastens itself to the wings, 

 wing pads or abdomen and uses its mouth parts to suck up the 

 fluid portions of its host. In a short time its body increases in 

 size, the legs grow smaller, and the mite resembles a small, glob- 

 ular mass of blood attached to the locust. Sometimes as many as 

 twenty mites can be counted on a single host. When thus in- 

 fested, the locust often becomes disabled, and drags itself about 



Fig. 17. Trombidiutn lociislariun Riley. a, mature larva when about to leave the 

 wing of a locust; b, pupa; c, male adult when just from the pupa; d, female the 

 natural sizes indicated to the right; c, pupal claw and thumb; /, pedal claws; g, one 

 of the barbed hairs h, the striations on the larval skin. (After Riley.) 



in a clumsy fashion, eats less and dies early, often befoie the mat- 

 ing and egg-laying season has arrived. In the swollen and almost 

 legless condition which the mite soon attains, it can not move 

 about, and so remains in one position until full grown, when it 

 drops to the ground and enters the pupal stage from which it 

 emerges as the "red spider-kin" of spring. It often becomes ma- 

 ture in late autumn and passes the winter in the ground where it 

 is not idle, except when the temperature sinks below the freezing 

 point. It feeds upon all sorts of soft food, and whenever it has 

 access to the eggs of locusts it greedily eats them. In soil con- 

 taining eggs of locusts large numbers of these mites congregate. 

 They creep into every hole in search of these eggs and thrive upon 

 such rich food. The great advantage 1 of fall plowing over all 



