ATTACKING THE LEAVES. 



555 



Fig. 366. 



No. 217.— The Red Spider. 



Tetranyclius ielarius (Linn.). 



This is a very small mite, which often proves a serious pest 

 to gardeners, especially to those who cultivate })lants under 

 ^lass. Occasionally, in dry weather, it attacks the leaves of 

 the black currant and destroys them. Fig. 366 represents 

 the male of this species, very much 

 enlarged, the mite itself being 

 scarcely visible to the unaided eye ; 

 the small dot within the circle at 

 the side of the figure indicates the 

 natural size of the insect. It spins 

 a web on the under side of the 

 leaves, of threads so slender as 

 to be scarcely visible even with 

 an ordinary magnifying-glass until 

 woven into a net-work. Under 

 this shelter will be found a colony, 

 consisting of mature individuals of 

 both sexes and young mites of all 

 ages. By the aid of their jaws, 

 which are not unlike the beak of a bird, they tear awav the 

 surface of the leaf, and plunge their beaks into the wound 

 and suck the juice. 



The egg of this mite is nearly round, and colorless; the 

 larva is a minute, transparent object, not unlike its parent, 

 but it has only six legs, and creeps along slowly. The mature 

 mites have eight legs, and vary much in color, some being 

 greenish marked with brown specks, others rust-colored or 

 reddish, and many of them brick-red. 



The leaves attacked soon indicate the presence of this in- 

 vader by their sickly hue; the sap being sucked by a mul- 

 titude of tiny mouths, they soon assume a yellowish cast, 

 with patches of a grayish or lighter shade; and if the mite is 

 allowed to pursue its course unchecked, the foliage becomes 



