388 JOURNAL OF THE "ROYAL HORTICULTURAL SOCIETY. 



Common in Europe, North America, and Cuba, and is known also as 



Trametes radiciperda. 



Sacc. Syll. vi. 5487 ; Mass. PI. Dis. 183, fig. 41 ; Cooke, Hdbk. No. 

 788; Hart, d Som. Dis. Trees, p. 187, figs. 119, 120; Marshall Ward, 

 Timbers &c, p. 142, figs. 11-12. 



Douglas Fie Blight. 

 Botrytis Douglassii (Tub.). 



Seedlings and young trees of the Douglas Fir and Welling tonia are 

 liable to have their leading shoots destroyed by this mould, which makes 

 its appearance as a brownish-grey mould on the branches, which soon 

 curve and die. The threads are brownish, either solitary or in tufts, 

 branched towards the summit, with the branchlets dilated, and toothed 

 or spinulose at the tips. Conidia grouped in heads, oval, colourless, 

 9x6^. Minute sclerotia are formed on the dead branches. 



With rather more zeal than judgment, Mr. Massee has called this 

 species Sclerotinia Douglassii, although he does not know that a Peziza 

 cup or sclerotinia has ever been produced, only that it might have been. 

 He seems to have forgotten that biology is a science of facts, and not of 

 dreams, and that we have no right to assume a fact until it can be 

 proved. Moreover, we have every reason to believe that this is no other 

 than Botrytis drier ea. 



Known also in Holland and Germany. 



Spraying with Bordeaux mixture at an early stage would destroy the 

 conidia and check the disease. When badly infected the plants should be 

 burnt at once. 



Sacc. Syll. x. 536; Mass. Pi. Dis. p. 160; Hart. & Som. Dis. Trees, 

 p. 130, fig. 71. 



Hypoderma nervisequum (DC). 



Is a common disease on the leaves of the Silver Fir in the Erzgebirge. 

 The leaves become yellowish-brown on the under side ; the midrib bears 

 a black longitudinal ridge. 



Hart. & Som. Dis. Trees, p. 108, figs. 52, 53 ; Sacc. Syll. ii. 5787. 



Spbuce-Leaf Redness. 

 Hypoderma macrosporum (Hart.). 



Is produced on the leaves of the Spruce, also in the Erzgebirge, and in 

 Switzerland. 



Hart, dt Som. Dis. Trees, p. 109, fig. 51 ; Sacc. Syll. ii. 5789. 



Spruce Shoot Disease. 

 Septoria parasitica (Hart.). 



This new disease has manifested itself on the Continent in young 

 Spruce woods and in seed-beds. 



Hart. & Som. Dis. Trees, p. 143, figs. 81, 82. 



