162 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
fig. 28). The conidiophore is slender, 2-3 p in diameter, either simple 
or branched, and bears laterally several to many conidia irregularly 
distributed along its length. The conidia are thin-walled, hyaline, 
cylindrical or slightly curved, 1.8-2.6 p in diameter by 4.5-6.7 p in 
length, and average 2 X 5.5 p (pi. 19, fig. 29). They arise with but 
slight regularity of sequence or position as lateral, branch-like out¬ 
growths from the conidiophore, and are generally of the same diameter 
with it. Each conidium is cut off by a curved septum, and soon falls 
away, at first leaving a depression in the conidiophore corresponding 
to its convex base (pi. 19, fig. 29). When the conidiophore is immersed 
in the nutrient drop, or rests on its surface, the conidia show a tendency 
to assume right and left positions parallel to the surface of the drop (pi. 
19, figs. 28, 30); but when the fertile hypha extends out into the air 
the conidia are produced radially on all sides of the conidiophore (pi. 
19, fig. 32). In any case there is a tendency for adjacent conidia to 
assume a parallel direction in groups of two or more. As the old 
conidia fall aw T ay new ones may develop from other parts of the 
conidiophore (pi. 19, fig. 29) or all may mature at once without any 
subsequent growth. The total number of conidia produced on a 
single conidiophore varies from one to more than twenty. 
After the formation of conidia, the conidiophore soon loses its pro¬ 
toplasm and disappears, but a single conidium is frequently first cut 
off from its distal end (pi. 19, fig. 30). In exceptional cases, a con¬ 
siderable length of the old conidiophore may, after the formation of 
the lateral conidia, break up into a chain of two or more spores, thus 
resembling the formation of oidia (pi. 19, fig. 31). 
Germination of conidia .— Germination begins at once in cell cul¬ 
tures, the conidium swelling enormously and giving off two or more 
germ tubes. The whole conidium may enlarge and become lemon¬ 
shaped or nearly spherical (pi. 19, fig. 33a), but more frequently the 
swelling is unequal at the two ends and the spore becomes pear-sharped 
(pi. 19, fig. 33b). In the former case germ tubes are usually given 
off from both ends at once (pi. 19, fig. 34a), while in the latter the first 
germ tube appears at the larger end and may be subsequently followed 
by one or more others from the sides or smaller end (pi. 19, fig. 34b- 
34c). 
The germ tubes develop into small-sized, clampless hyphae consti¬ 
tuting a primary mycelium which is not externally distinguishable 
from that arising from a basidiospore. In certain respects, however, 
