‘ 
432 ° u SECOND PART.—MYCETOZOA. 
:The conformation of the sporangia in Stemonitis runs differently in one respect 
from that of all other known forms. The slender threads of the plasmodium, which 
lives in rotten wood, unite at first into large cylindrical or ellipsoid bodies of 
homogeneous protoplasm, which rest their broad surface on the substratum. Then 
a hollow cylindrical firm central column is separated off in the protoplasmic 
body, and rises vertically from a membranous base resting on the substratum, 
advancing by acropetal growth (Fig. 186 a, 4). The mass of protoplasm, the 
longitudinal axis of which is traversed by the column, stretches at first at the same 
time in the same direction; but it afterwards loses hold of the substratum at its base 
and clinging to the central column moves on it a certain distance upwards till at 

a 
ce 
FIG. 186. Stemonitis ferruginca. a a com- FIG, 18. Ceratium hydnoides. Forming of 
mencing sporangium with the first beginning of the sporophores on plasmodia which have come to the 
central column. & sporangium which has reached surface of a piece of wood. Successive stages of 
its mature form, capillitium and spores not yet formed: development according to the letters a—c; ¢ the 
Both figures represent specimens in optical longitu- mature state. After Famintzin and Woronin, about 
dinal section hardened in alcohol and then rendered 3 times the natural size, 
transparent in glycerine. zmagn.ıztimes, 015 times. 
length it becomes stationary and developes into a sporangium in the usual manner 
(Fig. 186 4). The sporangium is supported on the lower portion of the central 
column which is laid bare by the upward movement of the protoplasm, as on a stalk. 
Other genera allied to Stemonitis behave in a similar manner. Further details must 
be sought in the different monographs. 
The plasmodia of the ectosporous Ceratium hydnoides come forth to the 
surface from the interior of the rotten wood which is their habitation to form their 
spores (Fig. 187). Here they appear at first to the naked.eye as white cushion-shaped 
bodies (Fig. 187 a); examination with the microscope shows that these cushions are 
formed of countless microscopically slender plasmodium-branches, united together in 
every direction into a net-work of narrow meshes, such as is shown in Fig. 188 a. The 
meshes are filled with a hyaline homogeneous gelatinous substance of watery 
consistence, which forms a thin coating on the surface of the net-work. To form 
the sporangia cylindrical often dichotomous outgrowths, resembling the spikes of a 
Hydnum and growing to be a few millimetres in length, rise erect from the surface 
of the cushion (Fig. 187 4, ce). The whole body of protoplasm moves into these 
outgrowths, leaving only a thin flat layer to connect it with the substratum. During 
