FUNGOID PESTS OP CULTIVATED PLANTS. 113 



of the conidia. It is reported that this is a wound parasite, and enters 

 the stem through wounds made by pruning, finally causing discoloration 

 in the centre of the stem (see figs. 13 and 14). The trees will continue to 

 grow for several years after infection. 



Destructive to Apple and other fruit trees, especially Plum and 

 Cherry. 



Sacc. Syll. i. 566 ; Cooke Hdbk. No. 2460 ; Journ. B.H.S. (1902), 

 xxvi. p. 742, fig. 313 ; Ibid, xxvii. pp. 691, 936, 1152 ; Gard. Chron. 1902, 

 p. 235, fig. 80 ; Berlese Icon. iii. pi. 85. 



BROWN ROT. 

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



This rot is not confined to the Apple and Pear, but attacks most 

 orchard fruits, especially the Cherry, to which we shall refer it later on. 

 (See "Apricot Brown Rot.") 



Thilm. Pom. p. 22 ; Journ. E.H.S. (1902), p. 738, fig. 311. 



FRUIT SPOT. 

 Septoria Ealfsii (Berk.). 



About the year 1854 Berkeley described a small fungus which 

 accompanied spotting on ripe Apples ; but it never seems to have been 

 demonstrated that it was the cause of the spotting, and as nothing has 

 transpired since which leads to the conclusion that it is really a fruit 

 disease we can dismiss it with a brief notice. 



The appearance caused is that of black patches of an irregular form 

 on the surface of ripe Apples. Over these patches are scattered the minute 

 points, which indicate the receptacles of the fungus. The sporules are 

 long and slender (30 /* long) with six minute nuclei. Pears as well as 

 Apples are said to have suffered from the same infliction. 



Sacc. Syll. iii. 3028; Cooke Hdbk.,^Q. 1307; Berk. Ann. N. H. 

 No. 745, t. xv. f. 6 ; Thilm. Pom. p. 122! 



APPLE SCAB. 

 Fusidadium dendriticum (Wallr.), PI. X. fig. 3. 



This disease appears under different forms, but in all cases it seems 

 to be caused by the same fungus. On the leaves it comes in small olive 

 spots, which are somewhat rounded and gradually enlarge, and become 

 velvety and irregular ; frequently two or three spots will run together 

 and form a large irregular blotch. The mould also appears on the 

 petioles and the young twigs. The threads of which the mould is com- 

 posed have a radiating habit, from which its specific name is derived. 

 On the fruit its appearance is similar, but as the spots increase in size 

 the cuticle cracks and forms a light-coloured ring about their margin. 

 The greatest vigour is towards the edge of the spots, where the fruit 

 seems stimulated to the production of ,a kind of corky layer in its efforts 

 to throw off the disease and the formation of scab. Generally the result 

 is to produce on the fruit crackings with a thickened scabby edge. 



The mycelium is rather superficial, and produces short erect brown 

 threads at the apex of which the spores, or conidia, are produced. These 



i 



