Explanation of Plates 261 



Plate 4 



Figs. 64-68. U. Sengokui ; 64, perithecium with appendages, X 150; 65, 66, three 

 appendages ; 67, asci and ascospores ; 68^ part of outer wall of perithecium. 



Figs. 69-72. U, fraxini ; 69, perithecium with appendages X ^5^; 70, single ap- 

 pendages, and the apex of three others ; 71, asci and ascospores ; 72, part of wall of 

 perithecium. 



^igs. 73-78. U. salicis var. Miyabei^ 73, perithecium with appendages, X ^S^; 

 74, 75, three appendages; 76, 77, branched apex of two appendages; 78, asci and 

 ascospores, 



Plate 5 



Figs. 79, So, U. prunasiri^ appendages, asci and ascopores. 

 Figs. 81, 82. U. Clintonii^ appendages, asci and ascopores. 

 Figs. %'^, 84, U. flextwsa^ two appendages and germuiatuig conidium. 

 Fig. 85. U, salicis J helicoid apexof four appendages, from specimen on Popiilus 

 bahamifera (** U, heUciformis^''^. 



Fig. 86. U, necator, base of an appendage, showing abnormal enlargement, from 

 specimen on Adinidia from Japan. 



Fig. 87. U, acerist apex of ^"^^ appendages {a, slightly flattened). 



Fig. 88. U. Delavayiy asci and ascospores. 



Fig. 89. U, poiyckaefa, asci and ascopores. 



Figs. 90, 92. Oidium-like fungus occurring with the mycelium of U. acert's, var. 

 Ttilasnei ; 90j conidiophores ; 92, conidia. 



Fig. 91. Oidium occurring on the same leaf with the above. 



Fig. 93. U. dandestina, appendage and asci. 



P'igs. 94, 95. U. Australiana^ two appendages, asci and ascopores. 



Figs. 96, 97. Fodosphaera oxyacani/iae, appendage from European specimen on 

 Crataegus Oxyacantha ; a, b^ c, successive stages in the development of the young ap- 

 pendage. 



Fig. 98. P. biuncinatay apex of three appendages. 



Plate 6 



Figs. 99-108. P, oxyacanthae^ apex of appendages and asci ; 99, 100, from spec- 

 imens on Pyrus Aitcttparia ( " P. aucupa}iae^^)', loi, 102, from American specimens ; 

 103, 104, from specimens on Pyrus Germanica (*' P. Claiidestina''^ ex herb. L^veille); 

 105, from specimen on Spiraea salidfolia {^^ Microsphaera ftdvofulcra'*'' ); 106, 107, 

 loS, three asci, showing variation in size. 



Figs. I09-II4. P. oxyacanthae var. tridactyla^ apex of appendages, ascus and 

 ascospores. 



Fig. 115. /*. oxyacantkae^ conidial {^Oidiitm) stage showing conidiophore and 

 conidia. 



Figs. 116, 117. Sphaerotheca kumuli (on Spiraea ulmaria), conidial [Oidium) 

 stage (116, portion of a leaf, showing mycelium and five conidiophores, X ^5*^ 5 ^^7t 

 single conidiophore and conidia). 



Fig. IlS. Podosphaera Schlechtendalii^ ascus and ascospores. 



Plate 7 



Figs. 1 19-122. Fodosphaera leucotricha ; 119, I20, two perithecia, with apical and 

 basal appendages, X 95 5 ^^l, ascus and ascospores; 122, branched apex of two ap- 

 pendages. 



