54 
D. D. CUNNINGHAM. 
in nutritive material, the mycelial development undergoes various 
modifications, and where nutritive material is absent, as in dis- 
tilled water, many conidia refuse to germinate ; and, in those 
cases where germination occurs, the germinal tubes are abortive, 
their growth being arrested so soon as the store material of the 
parent conidia is exhausted. The mere addition of moisture is 
sufficient to induce germination in many fungal spores and 
conidia, but where nutritive material is wanting, or where the 
means providing for its assimilation are absent, the amount of 
growth which takes place is determined by the amount of ma- 
terial stored up in the reproductive body. The phenomena 
observed in regard to the conidia of Choanephora afford an 
example of the result of absence of nutritive material, whilst 
those recorded regarding the germination of lichen-spores apart 
from algal elements appear to be referable to absence of assimi- 
lative capacity. 
The germinal tubes and actively-growing young mycelial fila- 
ments of Choanephora are full of a shining protoplasm, in which 
sap vacuoles are present in varying numbers. "When examined 
under high powers, the protoplasm presents a dimly clouded 
aspect, and a small number of brilliant, sharply-defined granules 
are seen scattered through it at wide intervals {vide fig. 1, a). 
Fig. 1.— Germinal tubes of Choanephora. x 1000. A. Healthy 
tube. B. Starved tube. 
In such tubes it is almost impossible to detect any movement 
in the protoplasm, as, owing to the fulness of the tube and the 
general absence of distinct granules, there is nothing to serve as 
an index of movement save the slow changes in the form and 
distribution of the vacuoles. In older portions of mycelium, 
however, an abundance of granular matter accumulates, and 
here active streaming of the protoplasm is very distinct in many 
cases. Granular accumulation increases rapidly preparatory to 
the development of the fertile filaments, and these and the young 
