454 DISEASES OF CULTIVATED PLANTS 



fall early in the season. Later in the season, the sunken, 

 reddish areas on the tips of the branches indicate the disease 

 on those parts, and Sorauer has shown that in the latter 

 places the disease may readily pass the winter. In this 

 country Fairchild has also corroborated these views. The 

 premature hardening or ripening of the young wood prevents 

 the budding operation ; or if budding is not entirely pre- 

 vented, the early cessation of growth in the formative 

 cambium of the stock renders a perfect union of the woods 

 difficult to secure. 



The results of all properly conducted experiments upon 

 nursery stock indicate that Bordeaux mixture as a fungicide is 

 essential to success where this disease prevails. 



Duggar, B. M., Cornell Univ. Agr. E.xp. St., U.S.A., 

 Bull. 145 (1898). 



Sorauer, P., Zeitschr. Pflanzenkr., 2, p. 372, pi. 16 (1886). 



CORYNEUM (Rees) 



Spore-beds discoid or pulvinate, subcutaneous, erumpent, 

 compact, black ; conidia oblong or fusoid, 2 -many-septate, 

 smoky ; basidia filiform. 



Gummosis of stone fruit-trees. Peaches, cherries, apricots, 

 almonds, plums, etc., are often severely injured by a fungus 

 known as Coryntum beyerinckii (Oudem. ). Quite early in 

 spring, when the leaf buds are just expanding, small red 

 patches appear on the under surface of the leaves. These 

 patches increase in size for some time, and about June little 

 black specks, composing the fruit of the fungus, appear 

 scattered over the red patches. The patches are small and 

 fairly circular in outline, and after the spores have been 

 produced, become dry and drop out of the leaf, leaving a 

 number of circular holes which are usually attributed to the 

 action of the ' shot-hole ' fungus ( ( 'ercospora cireumscissa ). The 

 fungus also attacks the young shoots and forms more <>r less 

 elongated spots, below which the tissue is killed to the centre 

 of the shoot. It is considered by some that the gumming of 

 stone fruit-trees is caused by the Coryneum, and there certainly 

 is frequently a collection of gum close by the wounds caused 

 by the fungus, but on the other hand gummosis frequently 

 occurs in the absence of Coryneum, so that it is probable that 



