112 
(Pl. XVIII). It is so brittle that by gently tapping the cover-glass over 
conidia the outer dark wall of every one of them may be broken in frag- 
ments, much as a peanut is broken if stepped upon. This character 
is common to H. Nos. 1, 3, 5, 13-16, etc., as well as to H. No. 2, and many 
other species, though in some the wall is less brittle than in others. The 
conidial wall that is left after the solution of the endosporium by sulfuric 
acid is entirely without sign of septation, but shows the apical spot clearly 
differentiated as a thin pale region. 
Fic. 10.—Variation in conidial shape and septa- 
tion of H. No. 1, and showing also the dark spot, 
stipe, at basal end, and the pale apical spot. 
Conidial contents.—Within the thin colored wall are the protoplasts, 
usually several in number (Fig. 11), and between the protoplasts and the 
outer wall is a thick hyaline layer of substance that is somewhat soft, usually 
appearing almost gelatinous (Pl. XVIII). This hyaline soft layer represents 
morphologically, I believe, a second cell-wall, the endosporium of de Bary 
(9). I shall so speak of it. That this wall is soft is shown by the way the 
conidial contents issue from the end of a cracked conidium under pressure 
