354 ARACHNOIDEA. 



CASE 



XVI. Section L— Species Living in Buds. 



j^P, Phytoptus taxi (Tetranychus taxi, Murr., in Gard. Chron. 1875). — I. 

 », 2, 3, 4. Sketch of twig with buds attacked by it ; 2. Magnified figure of the 



insect ; 3. Magnified diagram of section of injured bud ; 4. Microscopic 

 slide containing this section. 



This species was first noticed in the spring of 1875 by Professor 

 Thistleton Dyer, who found it doing considerable damage to the 

 yew hedges in the neighbourhood of London, by destroying the 

 young buds and preventing a fresh growth. The buds looked as if 

 they had been frost-bitten, and on breaking them open they were 

 seen to be swarming with Phytopti — so minute, however, as not 

 to be discernible vath the naked eye. The texture of the skin 

 of the leaflets in the bud was seen to be injured, and it made no 

 progress. We described it, with doubt, as a Tetranychus, it being 

 at the time we did so, the general opinion that Phytopti were the 

 larvae of that genus. We are no longer of that opinion. 



Nos. Phytoptus coryli {Frauenf., Verh. Zool. & Bot. Gesel. in Wien. xv. 895), 



^'^' (Calycophthora avellanae, AmerL, Lotos, 1863, p. 44). — 5. Specimens 



of twigs with buds attacked by it (2) ; 6. Sketch of ditto. 



This was first observed by Dujardin (Ann. des Soc. Nat. 185 1). 



It is also not improbable that it is the same as Dr. Amerling's 

 Calycophthora avellanse, of which Kaltenbach says : — " This mite, 

 according to the observations of Dr. Amerling, M. Kirchner, and 

 ourselves, deforms the leaf buds into cone-shaped scaly galls, 

 which fade early, and never unfold or produce fruit." The buds 

 here ar^e swollen and rounded. 



No 7. Phytoptus persic^.— 7. Sketch of twig attacked by this species. 



At Montreuil, near Paris, which is celebrated for its cultivation 

 of peaches, the peach trees are at times attacked by a disease, 

 which is known there by the name of " the miller " (le meunier). 

 The disease consists of a sort of white dust, which covers all the 

 peach trees. In 185 1 M. Guerin Meneville pointed out (Ann. 



