DIPLODINA 429 



at the base of the shoot where it is enveloped by the scales 

 of the terminal bud of the previous year. During the summer 

 the fruit of the fungus appears under the form of small black 

 points on the shrunken shoot ; they are often to be found at 

 the base of the shoot only, concealed by the bud-scales, or 

 they may be abundant at the withered apex of the shoot. 



The conceptacles are black and very minute, resembling 

 tubercles or sclerotia, one or many-celled, the cavities lined 

 with long, slender conidiophores, each bearing a hyaline, fusi- 

 form, i-septate conidium, averaging 13-15 ft long. 



Hartig, Zeitschr. f. Forst. und Jagdw., Nov. 22, 1890, 

 p. 668. 



Hartig and Somerville, Diseases of Trees (Engl, ed.), p. 143 



(1894). 



Prillieux, Malad. des Plantes Agric, 2, p. 292 (1897). 



Sweet chestnut canker. Young sweet chestnut-trees, also 

 the shoots that spring from stumps of trees that have been 

 cut down, often suffer from a disease that much resembles in 

 general appearance apple canker, caused by Nectria ditissima. 

 The disease is best known in the neighbourhood of Limoges, 

 in France, where the chestnut undergrowth, used for binding- 

 hoops, is an industry of importance. The disease, known 

 locally as ' Javart,' appears on the bark of the shoots under 

 the form of elongated, very obvious patches on the bark, be- 

 ginning almost immediately above the stump, and soon 

 girdles the shoot. Several diseased patches are often present 

 on the first yard of the shoot from the stump. The bark 

 soon loses its normal colour, and presents the appearance of 

 having been severely bruised, and becomes brownish, de- 

 pressed, then dries up and cracks, and finally falls away in 

 patches, exposing the wood which is also injured. During 

 the autumn the diseased patches of bark are covered with the 

 conceptacles of a minute fungus, Diplodina castatieae (Prill, 

 and Del), which is the cause of the disease. 



Perithecia formed under the epidermis, conico-depressed, 

 wall blackish olive, the mouth piercing the epidermis, 

 300 X 150 /x, conidia fusiform, i-septate, not constricted, 6-7 

 X i-i'S /*, conidiophores acicular, 10-12 /x long. 



Is the American chestnut disease distinct from the present 

 one? 



Prillieux and Delacroix, Bull. Soc. Myc. France, 9, p. 275 



(1893)- 



