JOUENAL 



OF THE 



Royal Horticultural Society. 



Vol. XXVII. 1902. 

 Part II. 



PESTS OF THE FLOWER GARDEN. 

 By M. C. Cooke, M.A., LL.P., V.M.H., A.L.S., F.U.H.S. 



[Part II. with three coloured plates.] 



Evening Primrose Leaf-spot. 



Septoria (Enotheras (West.), PI. III. frg. 55. 



The living leaves of the Evening Primrose are subject to the attacks 

 of this parasitic fungus, not only in most parts of Europe, but also in 

 North America. 



The spots are rather small, rounded, at first pale greenish, then more 

 or less brown or bleached, margined by a vinous red band. They occur 

 chiefly on the upper surface, to the number of from six to ten, whilst a 

 quantity of dot-like receptacles are to be seen collected towards the centre 

 of the spots. 



The sporules are long and thread-like, mostly curved, and contain a 

 row of little nuclei (35-40 xH^), and the spots are traversed by the 

 mycelium. 



It is generally thought that in these leaf-spot diseases spraying with 

 Bordeaux mixture may be of service. At any rate the spread of the 

 disease may be checked by persistently destroying diseased leaves. 



Sacc. Syll. in. 2782 ; Grevillea, xiv. 101. 



Although the above is the only parasite upon Oenothera which has yet 

 appeared in this country, there are other species known, especially in 

 North America, such as sEcidium Peckii, and JEcidium (Enothcrce, Pac- 

 cinia Oenothera, and Pucciniastrum (Enotlierce, Uromyces Oenotheras and 

 Uromyces plumbarius, in addition to a rot-mould, or Peronospora. As 



B 



