249 
of Poronia punctata (Z.). 
vertically from the surface of the horizontal mycelium, which 
has grown upon and within the substratum. This stage is 
shown under a low-power objective in Fig. 8, in which must 
also be noted the presence of numerous crystals of calcium 
oxalate, which have been separated from the substratum 
(Fig. 9). Similar crystals were also found in hanging-drop 
cultures about eleven days after infection (Fig. 10). 
When the stromata have reached about half an inch in 
height they begin to expand at the top, and in some cases 
become considerably branched; in others, and this is the 
commoner case, the head continues to enlarge gradually into 
the form of an inverted cone or pegtop, and a flattish disk 
or cup-shaped surface is formed above, exactly comparable 
to those grown in nature. It is noticeable, however, that in 
these artificial cultures larger specimens were obtained than 
any which formed from the original material on horse-dung. 
In the former series several stromata measured 2-5, or even 
5 to 6 cms. in height, whilst in the latter none grew to more 
than 1 *5 cm. 
It was frequently remarked that if, in the transference of 
the cultures from one medium to another, a stroma was 
touched or injured in any way, rapid growth at once took 
place at the point of injury, and new stromata were quickly 
formed as lateral branches of the older one (cf. Fig. 5). 
At all points where growth is vigorous can be seen numerous 
drops of a pinkish or yellowish fluid ; this occurs, not only 
before the formation of a stroma, but also from the disk-like 
surface of the fully formed stroma, at the time of the 
formation of perithecia and asci. 
As these mature, the liquid drops dry up, and the black 
spots, indicative of the ripening perithecia, become visible. 
The copious exudation of liquid is a prelude to the for¬ 
mation of the perithecia and ascospores. The possibility 
of its having anything to do with the projection of the 
trichogyne-like hyphae referred to below cannot be denied, 
but, since no spermatia or fertilization could be discovered, 
it seems more probable that the process is rather comparable 
