1 86 DISEASES OF CULTIVATED PLANTS 



and the branch attacked dies beyond the point of infection. 

 When the disease is general the leaves towards the top of the 

 tree turn yellow, and soon afterwards the tree dies. In some 

 instances, especially during a dry season, the fungus does not 

 form fruit, but when the bark remains damp, numerous 

 minute, white tufts of the conidial form appear first, followed 

 by dense clusters of minute red perithecia, which under 

 favourable conditions often almost completely cover the 

 bark. 



Fusarium stage. Conidia fusiform, slightly curved, hyaline, 

 i-5-septate, length very variable. 



Ascigerous form. Perithecia subglobose, vermilion, 

 polished, shortly and obtusely papillate, not collapsing when 

 old, asci cylindrical, slightly constricted just below the apex, 

 shortly stipitate, 8-spored, 100-110X9-10 /u,; spores 

 i-seriate, elliptic-oblong, i-septate, constricted at the 

 septum, hyaline, 14-18x6-7 /*. 



It is suggested that diseased trees should be removed to 

 prevent the spread of the disease. This, however, appears to 

 be impracticable on a large scale. 



Hartig, Unters. aus dem Forstbot. Inst. zu Miinchen, 

 i. p. 88. 



Hartig and Somerville, Diseases of Trees, p. 89. 

 Prillieux, 2, p. 83 (1879). 



Coral spot disease (Nectria cinnabarina, Fries.) has usually 

 been considered as a saprophyte, and in many instances 

 certainly is such, covering dead branches, pea-rods, etc., with 

 its brilliant fruit. In other instances it is a true wound- 

 parasite, attacking various trees, sycamore, lime, horse- 

 chestnut, and more especially red currant. The numerous 

 bright, coral-coloured warts, about the size of a millet seed, 

 thickly studded over the surface of dead branches, are 

 familiar to most people. These are the conidial condition of 

 the fungus. During the winter these red pastules bear the 

 ascigerous condition of the fungus, the perithecia of which 

 are minutely warted and of a dull, brownish-red colour. 



Perithecia clustered on the pinkish conidial stroma, spheri- 

 cal, corrugated, brownish-red, asci 8-spored, spores oblong, 

 ends obtuse, i-septate, 14x5-6^. 



Conidial form (= Tubercularia vulgaris), coral-red, pulvi- 

 nate, conidia hyaline, 6-8 X 1*5-2 /*. 



