FUNGOID PESTS 



of conidia, each divided into five cells. This is supposed to be the first stage 

 of the Elm-leaf Blotch. 



Elm-leaf Scab (Piggotia astroidea) is thought to be the second stage. It 

 occurs as small blackish scabs on the upper surface of the leaves. The scabs 

 are composed of minute tubercles, from which conidia exude. 



Elm-leaf Blotch (PhyUachora Vlmi) is not unusual on Elm-trees, taking 

 the appearance of rounded, convex, nearly black blotches on the upper surface 

 of the leaves. The fungus matures after the fall of the leaves, the cavities 

 containing numerous cylindrical sacs or asci, each enclosing eight sporidia. 



Hawthorn Powdery Mildew (Podosphcera Oxyacanthce) frequently whitens 

 the leaves of Hawthorn, powdering them with the fallen conidia. The minute 

 receptacles have 8 10 shortly branched appendages, about equal in length to the 

 diameter of the receptacles. Each of the latter contains only one ascus, enclos- 

 ing eight sporidia. 



Hawthorn Cluster-cups (RcesteUa lacerata) is a species of fungus found 

 on the leaves, petioles, and fruits, taking the form of tufts seated on orange spots. 

 The flask-shaped or cylindrical peridia are much lacerated and fringed at the 

 margins, and ultimately split nearly to the base in reflexed thread-like filaments 

 of attached cells marked with wavy lines. The yellowish aecidiospores are nearly 

 spherical and warted. These cluster-cups are believed to be the first stage in 

 the life of the Juniper Jelly-rust (Grymnosporangium clavariiforme), and are often 

 now called by this Latin name. 



Hornbeam-leaf Blotch (Gnomoniella fimbriata) attacks the living foliage 

 in the form of black convex blotches containing receptacles, each terminating in 

 a spine-like neck, and enclosing oblong asci with eight sporidia. The conidial 

 stage is believed to be the Glceosporium Carpini, a form of anthracnose in which 

 the cylindrical conidia are expelled in whitish tendrils. 



Laburnum Leaf-spot (Phyllosticta ( 'ytisi) takes the form of brownish, circular 

 spots, over which are scattered the dot-like receptacles containing curved 

 sporules. 



Larch Canker (Dasyscypha calycina or Peziza Willkommii). The Larch 



disease is thought to be caused by this Peziza, which is found on the twigs and 



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