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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



is likely to do much damage in nurseries, and I think you will 

 admit that a strong case is made out in favour of the need for 

 care and further observations as regards the weeds growing in 

 the neighbourhood of all places where Pines are cultivated from 

 seed. 



11. The Fms. 



I take this group in the broadest sense, including in it the 

 genera Picea (the Spruces), Abies (the Silver Firs), Tsuga (the 

 Hemlock Firs), and Pseudotsuga (the Douglas Fir). Much that 

 has been said of the Pines is also true of these predominantly 

 mountain trees. I shall therefore pass at once to the description 

 of the diseases due to fungi, merely remarking that those maladies 

 traceable to unsuitable climate, soil, atmosphere, &c., are much as 

 before. 



Here, again, some of the most disastrous forms of disease are 

 those due to hymenomycetous fungi which rot the timber, such 

 as Agaricus melleus, Trametes radiciijerda and T. Pini, Poly- 

 poriis vaporarius, P. borealis, P. f idvus, kc, and it is scarcely 

 necessary to add anything to what was said of these when 

 treating of the Pines. 



Again, also, it happens that, with the exception of PJiyto- 

 phtJiora omiiivora, which destroys the seedlings of Spruces and 

 Silver Firs, the disease-inducing fungi all belong to certain 

 sections of the Hymenomycetes, Ascomycetes, and especially the 

 Uredinese.* 



Undoubtedly one of the most extraordinary of all these 

 forms is Calyptospora Gceppertiana, a uredinous fungus which 

 alternates between the Silver Fir {A.2^eci7iata), on the leaves of 

 which it develops an ^cidial form long known as Mcidmm 

 colum7iaw, and the Ked Whortleberry {Vacciiiium Vitis-idcBo), 

 a common undershrub in the German Fir-forests, the stems and 

 leaves of which it distorts and kills by means of the mycelium 

 of its Uredo-form (known as Calyptospora — or Melampsora — 

 Gceppertiana). 



So far as I am aware, this form has not yet been met with 

 in this country,t but it does much damage on the Continent, 



* The general application of these remarks to Coniferae as a whole may 

 have to be modified when Ustilago FussH (Niessl.) on species of Juniperus 

 has been properly investigated. (See Soraner, vol. ii., p. 209.) 



f Plowright ("Brit. Ured. and Ust.," p. 271) states that he has found a 

 similar form {JEc. pscudo- columnar e) on various Silver Firs in England. 



