IT. JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



An anthracnose attacks the leaves of the Quince (Glceosporhun 

 Cydonia) in Southern Europe, as well as two or three kinds of leaf-spot, 

 and Oidium Cydon'ue in Italy. 



Medlar White Mould. 

 Oidium mespilinum (Thiim.). 



This white mould occurs on the living leaves of Mespilus in Austria, 

 forming broad white thin patches on the upper surface, which consists at 

 first entirely of an epiphytal web of mycelium. From this shortly arise 

 the fertile branches, which are at first simple and club-shaped. After- 

 wards two or three elliptical cells or conidia are cut off from the upper 

 portion of the branches, and form the short chain of spores (10 x 6 fi) 

 which ultimately acquire a pale grey colour. 



It is clear that this is an epiphyte of the same character as the 

 various species of Oidium which precede such mildews as that which 

 attacks the Hop, Rose, Gooseberry, Maple, Garden Pea, and many other 

 plants. 



In the case of any trouble the application of dry powdered sulphur is 

 the safest remedy. 



Sacc. Syll iv. 208 ; Grevillea, xvi. 58. 



Another white mould (Ovularia necans) has damaged Quince and 

 Medlar trees in Italy and France. Two kinds of leaf-spots are known on 

 Medlar leaves, but neither is recorded as British. Phyllosticta mespili 

 and Septoria mespili are both of them European. 



Plum Powdbri Miu>i:w . 

 Uncinula pruuastri (DC), PI. XI. fig. 17. 



This mildew resembles externally the previous species so much that it 

 is scarcely possible to detect the difference by the naked eye. However, 

 it is more commonly found on the wild Sloe than on the cultivated Plum. 



The mycelium is thin, and spreading over the surface of the leaves, 

 giving them a frosty appearance, but never very dense. The conidia, in 

 tin early stage, are of the Oidium form, and are produced in short chains. 



The receptacles are globose and minute, scattered over the mycelium, 

 and Mara Iv visible to the naked eye. The appendages which surround 

 the base of the receptacles are very numerous and peculiar in their 

 character, inasmuch as they are unbranched and curved at their tips in 

 a hook-like manner, and are about twice as long as the diameter of the 

 red ntacle. Each receptacle contains from twelve to sixteen transparent 

 IN ar -maped .acs, or asci, each of which contains six sporidia. 



Tin- sjmc'h i found also in France, Belgium, Germany, and Italy. 



As an cpiphUc, should this species threaten to give trouble, it should 

 be m« t with i he uilphur treatment. 



Sacc. Syll. i. 2« ; Cooke M. F. 289. 



