PESTS OF THE ORNAMENTAL SHRUBBERY. 3 



Germany, and Asiatic Siberia. It is known as Chrysomyxa rhododcndri 

 (DC). Teleutospores (10--14 /i broad) obtusely rounded above. Uredo- 

 spores warted, orange-yellow (17-28 x 15-22 /j). 

 Sacc. Syll. vii. 2660. 



Leather-leaved Bristle Spore. 

 Pestalozzia Guepini (Desm.). PI. XIV. fig, 17. 



This disease attacks numerous plants with coriaceous leaves, besides 

 Rhododendrons, such as Hoya, Camellia, Citrus, and Magnolia. 



Greyish spots are formed on the leaves, often near the apex, usually 

 with a distinct and perhaps elevated margin. The pustules are scattered 

 like little black specks over the spots. The conidia are large, produced 

 within the pustules, and extruded when mature. They are somewhat 

 narrowly elliptical (20-25 /x long), attenuated at each end, and divided by 

 three or four transverse septa ; the end cells smallest, conical, and colourless, 

 and the intervening cells brown. The apical cell furnished with three or 

 four long divergent hairs, as long as the conidia, the basal cell attached to 

 a colourless footstalk or peduncle. 



Diseased leaves should be collected and burnt before the sporules are 

 matured. 



Sacc. Syll iv. 4146 ; Cooke, Hdbk. No. 1401 ; Mass. PL Dis. p. 432. 



Oleander Leaf-spots. 



On the Continent, where Nerium Oleander is cultivated much more 

 extensively than in this country, its pests and parasites are of far more 

 interest, whereas w T e have no record of a single occurrence. 



Phyllosticta nerii has rather large sporules (15-18 x5-6 fx). 



Ascochyta oleandri, with septate sporules rather smaller (11-15x2— 

 2^). 



Septoria neriicola has short thread-like sporules, and so also has 

 Septoria oleandrina, both of which are known in Italy ; and Bhabdospora 

 oleandri which is parasitic on the twigs, and not upon the leaves, in 

 Algeria. The latter is apparently the Septoria oleandri of Montagne.' 



Arbutus Leaf- spot. 

 Phyllosticta arbuti (Desm.), PI. XVI. fig. 2. 



The parasites of the Strawberry tree are, for the most part, conn nod 

 to the ordinary leaf-spots of small importance, and of these the most 

 common is the above-named, which forms small dingy spots scattered over 

 the leaves. 



The receptacles are very small and sprinkled like little dots over the 

 upper surface of the spots, sometimes densely clustered together. The 

 sporules are also very minute, ovoid, and colourless (5 x3/i), often exhibit- 

 ing two small nuclei. The attacked leaves are in most instances at firs! 

 fading. 



This has been recognised in France and in Britain. 



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