RED SPIDER. 293 



activity upon the surface of the fluid as upon the 

 slug itself. 



RED SPIDER.* 



IN the summer of 1844, the gardener at Bottis- 

 ham Hall directed my attention to a peach-tree in- 

 fested with the red spider. The tree had a very 

 diseased appearance ; the leaves were red and spotted 

 on their upper surface, and fell prematurely, stimu- 

 lating the tree to put forth new leaves from the next 

 year's buds, and so subjecting it to great exhaustion. 

 On examining the leaves through a microscope, they 

 were found to be infested with a very minute mite, 

 scarcely bigger than the point of a pin, of an oblong- 

 oval form, with eight legs of not very dispropor- 

 tionate lengths, but the anterior pair a little the 

 longest ; the body of a yellowish orange-colour, 

 some specimens redder than others, and some with 

 an oblong dark spot on each side of the abdomen ; 

 the legs pale whitish, and transparent ; two eyes, 

 one on each side of the anterior part of the body, 

 forming a bright red spot. These mites were in all 

 stages of growth, and had evidently been bred upon 

 the leaves. The young were more pale-coloured 

 than the adult, which were often deep red ; the 

 former were also much more bristly than the latter, 

 the hairs seeming to wear off with age. Here and 

 there might be discerned (more especially on the 



* Acarus telarius, Linn. ; Tetranychus telarius, Duges, Ann. ties 

 Sci. Nat. (2nd ser.) torn. i. p. 25. 



