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CHAPTER XXIV. 



NOXIOUS INSECTS. 



'HE Vine is subject to, or becomes preyed on by, a great variety 

 \ of insects, which, by their persistent attacks, destroy the 

 vitality of the plant, if left unmolested. It is, therefore, of 

 great importance that the Vine cultivator should become 

 thoroughly acquainted with these pests their general appearance and 

 mode of life, the causes which may lead to their presence or 

 encouragement ; also the best and surest methods of preventing or 

 guarding against their attacks, and how to destroy them when, 

 unfortunately, they may appear. We shall now proceed to notice and 

 briefly describe the most injurious of them. 



The Red-Spider (Tetranyclius telarius), fig. 41. The annexed figure 

 is a greatly-magnified sketch of this insect, which is, perhaps, the 

 most troublesome of all, because of its being 

 so general. There is seldom a crop of Grapes 

 produced without some damage or other 

 being committed by this little pest. It is so 

 small that it is scarcely visible without the 

 aid of a magnifying glass, yet its whereabouts 

 is too easily recognised by the experienced 

 cultivator. It is of a pale red colour, and 

 spins fine webs on the leaves, chiefly on the 

 under-side, where thousands of the insects 

 may frequently be seen congregated, giving 

 the leaves quite a reddish brown hue. It is 

 this brownish or reddish appearance of the 

 leaves which often first betrays its presence. 

 The insects feed upon the juices of the plant, 

 especially those drawn from the leaves, which soon assume a sickly 

 yellow hue, and are either destroyed or rendered useless. Thus, 

 when the red-spider is allowed to feed upon and destroy the vitality 

 of the leaves, the result is equivalent to the absence of leaves ; and 

 without leaves there will be no eatable Grapes. The first appearance, 

 then, of this pest should be the signal for the commencement of 

 stringent measures for its eradication. 



As to the causes which tend to its introduction, the chief and most 

 fertile is dryness or aridity of the atmosphere, especially if produced 

 by fire-heat. Dryness at the roots will also encourage its increase, 

 and frequently it may happen that want of ventilation in hot weather 

 will favour its development ; that is, those parts of a Vinery which 



Fig. 41. BED-.SPIDER 

 (ENLARGED). 



