PESTS OF ORCHARD AND FRUIT GARDEN. 



27 



is caused by a wound parasite, which in its fully developed form is a 

 hymenomycetal fungus called Stereum purpureum. 



At the same time it has been affirmed on good authority that several 

 Horse Chestnut trees in Greenwich Park have been killed by attacks of 

 this same fungus, which has, at any rate, been developed freely on the 

 dead bark. 



Attacks Plum, Peach, and Apricot trees. 



We must still regard ourselves as sceptical as to whether the Stereum 

 is the cause of " silver leaf." 



Sacc. Syll. Hijm. ii. 7284 ; Cooke Hdbk. No. 910 ; Journ. Linn. Soc., 

 Bot. xxxv. p. 390, pi. x. 1902 ; Journ. B.H.S. xxvii. (1902), p. 712. 



ArRicoT Brown Eot. 

 Monilia fructigena (Pers.), PI. X. fig. 12. 



This disease attacks indiscriminately a number of pulpy fruits, the 

 Apple and Pear in this country, and the Cherry and Apricot in the 

 United States. In 1864, which was a very dry season, the Apricots in 

 many gardens were attacked. Fruits were in some cases spotted whilst 

 quite green, in other cases the attack did not seem to take place till they 

 were nearly ripe. The intermediate or half-ripe condition was apparently 

 that in which the attack was most prevalent. The first indication was 

 a little discoloured brownish spot, very slightly sprinkled with whitish 

 minute tufts of threads, on some of which a solitary spore might be 

 found. The subjacent tissue at this stage is traversed by multitudes of 

 thick, succulent, branched threads. The progress of the disease is rapid, 

 the brown spot increases in size, the centre is occupied by a dense mass 

 of mould consisting of closely set roundish tufts the threads of which 

 bear necklaces of spores, the central ones lemon-shaped, and as the 

 disease spreads the little tufts often assume a concentric disposition. At 

 length the whole fruit gives way, and either drops off or remains attached 

 to the tree, withered and wrinkled, like a large mouldy Plum (conidia 

 25 x 10-12 yu). (Fig. 7.) 



The methods hitherto recommended for this disease are to remove and 

 destroy all diseased fruit and to spray the trees, so as to prevent the 

 germination of all the spores which may be adhering to the bark. 

 Dissolve four pounds of sulphate of iron in five or six gallons of water. 



Gard. Chron. Aug. 27, 1864 ; Mass. PI. Dis. 300, fig. 79 ; Sacc. Syll. 

 iv. No. 157 ; Cooke Hdbk. No. 1812 ; Tubeuf, Dis. 497 ; Journ. B.H.S. 

 1902, xxvi. p. 738, fig. 311 ; McAlpinc Fung. Dis. p. 53, pi. viii. fig. 2. 



Walnut Anthracnose. 



Marsonia Juglandis (Lib.), PI. XII. fig. 26. 



This parasite on Walnut leaves has long been known in this country, 

 and certainly sometimes appears to take possession of nearly every leaf of 

 a full-sized tree. 



The spots appear on the under surface of the leaves, and are large, 

 often irregular in form, being limited by the veins of the leaves, generally 



