308 • ^'^^^^ BOTANICAL MAGAZINE. fvoi. xxx. no. mt. 



oil the diseased bark shows the compactly united mass of the 

 h\-phae under ]:)eriderm. These young stromata increase their size 

 little b}' little until thc\' reach the matured proper shape. The 

 shape of the matured stromata is ver^' different according to 

 their stage of development. The pycnidial stroma or ectostroma 

 has a special flask-like shape with rounded base. Such a special 

 morpholog3' of the ectostroma is an important feature of the 

 present fungus, separating it from other species of Valsa. 



In autumn the entostroma or the perithecial stroma is pro- 

 duced under the ectostroma, which is gradualh' displaced by 

 the growth of the entostroma and £it last takes complete pos- 

 session of its site. It happens not infrequently that the ento- 

 stroma is independently produced without an}- connection with 

 the ectostroma. The matured entostroma has a conical or 

 wart-like shape, having a round or elliptical base. In the 

 systematic studies on the genus Valsa, a great importance is 

 attached to the structure of the stroma, especially at its basal 

 portion. In the case of the present fungus, there is no black 

 boundarN' line, so called " conceptaculum ", between the stroma 

 and the host-tissue. The presence of such a boundary line is the 

 most essential character of the subgenus Leucostorna, which was 

 founded by Nitschke (1867)^'^ and accepted by manj' sub- 

 sequent authors. In the case of our present fungus, the stroma 

 is entirely composed for its upper part of the m\'celial-tissue, 

 while for its lower part mostly of the host-tissue, with the 

 mvcelium interminslinij in it. 



A section of the both kinds of the stroma shows a greenish 

 black or sometimes dark brown color. The average size of the 

 stromal is about 2.0—2.5 mm in diameter at base and 1.0—2.0 

 mm in depth. 



Pycnidia and Pycnospores. The pycnidium, even in the 

 matured stage, is a single unlobed cavity- which has depressed- 

 \y globose or napiform, forming the base of an ectostroma. 

 It has a black and thick wall which is not distinguishable 

 from the tissue of the stroma itself. The pycnidium has a single 

 exit and is about 1.5 mm in diameter and O.G nini in depth. 

 The pycnospores measure 2.85-8.75 x 0.88-1.75 « (commonly 



