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sphaera Junci ' as being allied to S. Veronicae. The terminal stages 

 in the life-histories of both these Fungi are strikingly similar, the 

 wedgeshaped spores being collected into spherical balls, the soro- 

 spheres, although in the case of S. Junci many of these balls are 

 of elliptical shape, and often merely loosely aggregated masses of 

 spores fill the root-cells. The stages of nuclear division in both 

 parasites are also similar. In old infected roots the cortical cells 

 contain the nucleated amoebae of the parasite, and in some the 

 nuclei may be seen collecting in masses previous to spore-forma- 

 tion. The infection of the root takes place by the entry of an 

 amoeba into a root-hair and thence into the cortex of the root. 

 The roots show no hypertrophy. This Fungus is in no way re- 

 lated to the Entorrhiza, which has been described by Weber in 

 Bot. Zeitschr. 1884, as being the cause of tubercle-formation in 

 the roots of Juncus bufonius. The latter is doubtless one of the 

 Ustilagineae ; its young spores are binucleate, and it infects the 

 root by means of conidia which push their way down the root- 

 hairs. I hope shortly to publish in detail an investigation into 

 the life-history of Sorosphaera Junci. " 



Shot-hole Fungus. (Cercospora circumscripta Sacc.). The 



Journal of the Board of Agriculture, London, June 1910, vol. XVII, 

 N 3, p. 211. 



This parasite attacks the leaves of the peach, almond, cherry, 

 apricot, and nectarine. Less frequently the leaves of the plum and 

 of other rosaceous trees are injured. 



Appearance of the Disease. The first indication of the disease 

 is the presence [of small pale-green, translucent [spots scattered 

 over the blade of the leaf. These spots gradually become more 

 cleardy defined, and increase in size up to a diameter rarely ex- 

 ceding one-sixth of an inch. When the patches commence to 

 turn yellow, the fungus bursts through the epidermis of both sides 

 of the leaf, in the form of very minute dark-coloured, hairlike 

 tufts or threads which bear the minute spores at their tips. At 

 this stage the diseased patches become dry and brown and drop 

 out, leaving circular holes, suggesting the idea of the leaf having 

 been riddled with small shot ; hence the popular name of " shot 

 hole fungus. " 



Remedies. Peach foliage suffers most from the " shot-hole " 

 disease in this country. In this case the disease is difficult to 



