122 PLANT DISEASES 



Dead and diseased seedlings should be removed and 

 burned. 



Hartig, Unters. aus dem Forstbot. lust., vol. i. p. i. 

 Hartig and Somerville, Diseases of Trees^ p. 78, figs. 



Rosellinia ligniaria, Nitschke. This fungus has been 

 observed by Mr. W. Carruthers, F.R.S., to attack living 

 ash-trees, eventually causing death. Specimens were 

 exhibited at the Linnean Society's meeting, December 16, 

 1897. 



GUMMOSIS OF ACACIA 



(PUospora gummipara, Oud. 

 = Coryneum gummiparum^ Oud.) 



Oudemans states that the production of Arabian and 

 Senegal gum is due to the presence of this fungous para- 

 site on species of Acacia. 



Oudemans, Hedwigia, 1883, pp. 131 and 161. 



HYPOCREACEAE 



ERGOT 

 ( Claviceps purpurea, Tul. ) 



This well-known disease is often abundantly developed 

 in the ears of various cereals, especially rye ; it also 

 attacks various pasture grasses. 



Inoculation takes place when the plants are in bloom, 

 the mycelium developing in the ovary, replacing the seed. 



