MITES. 205 



Family : Trombidiidse (Running Mites). 



Body four-cornered or longish oval; legs toler- 

 ably long, hairy; jaws claw or needle-shaped; surface 

 of the skin velvety; coloiu- reddish or yellowish. 

 They run about with great rapidity on the ground, 

 tree trunks, leaves, etc. Most species feed on the 

 juices which they suck from insects, or from other 

 arachnids. 



The Plant Mite, or Red " Spider " 



(Tetranychus telarius), 



is ovoid, at most one-fiftieth of an inch long ; reddish 

 (also yellowish or brownish), with a dark spot on 

 each shoulder. Plant mites are often found in con- 

 siderable numbers during the summer, especially on 

 the under sides of the leaves of low-growing plants ; 

 on garden beans, turnips, and hops; on several 

 ornamental plants, grasses, and various weeds ; on 

 roses, limes, horse-chestnut trees, elms, willows, and 

 fruit trees. In some exceptionally dry summers the 

 mite increases to such an extent as to become a great 

 pest. On the upper sides of the infested leaves 

 there is to be seen, besides the adult and immature 

 mites, a whitish, mealy substance, consisting of the 

 cast skins and whitish eggs. Many of the mites run 

 about here and there, but most of them remain fixed, 

 and suck the sap. All are covered by a delicate web, 

 which is formed by the animal. The attacked leaves 

 become limp, shrivel up, die, and fall off! In dicoty- 

 ledonous plants the withering generally commences 

 in the axils of the veins. The infested plants often 

 die off" gradually, but death may also take place with 

 great rapidity. Annuals are often killed by the 

 attacks of the mite. The mites pass the winter in 

 the ground, under fallen leaves, under the bark of 

 trees, etc. 



