156 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
mature spore has a thick wall consisting of an epispore, which is the 
wall of the original hypha and which also forms the walls of the stipe 
and the appendage, and an endospore which surrounds the inflated 
portion only. The endospore is formed during the period of concen¬ 
tration of the protoplasm. Therefore the stipe and base of the append¬ 
age frequently show thin, curving, transverse septa, abandoned as the 
protoplasm shrinks inward, which belong to the endospore and mark 
the successive stages in the concentration of the spore’s contents (pi. 
18, fig. 13). As the spore matures the color deepens and finally be¬ 
comes yellowish to deep reddish brown, the color being partly in 
the walls and partly in the spore contents. Usually the stipe is of 
lighter hue than the body of the spore, while the appendage is hya¬ 
line, although all three may be of the same shade. 
Among the mass of perfect spores may be observed many abnormal¬ 
ities (pi. 18, fig. 16-21). Occasionally the appendage is entirely 
. absent, or two are seen on one spore, or the single appendage although 
of normal diameter is branched one or more times. Again the append¬ 
age may retain the size of a sporophore, grow on irregularly, branch, 
and produce other spores which are sometimes separate and some¬ 
times more or less fused. Or the spore may enlarge and color normally 
but not form an endospore, the body of the spore remaining in open 
communication with stipe and appendage. Such a development re¬ 
sembles a paraphysis, a likeness which is still closer where the en¬ 
largement of the body of the spore is slight and the appendage has 
the diameter of a paraphysis. In fact, all gradations are found 
between normal spores and paraphyses, showing the morphological 
similarity of the two structures. 
Is the spore of Michenera artocreas a chlamydospore ?—This inter¬ 
pretation has been suggested by Peirce (’90) and Patouillard (’00). 
There is a very suggestive resemblance between the spores of Mi¬ 
chenera and typical chlamydospores, both in the appearance of the 
mature spores and in their method of formation. In both cases the 
protoplasm shrinks into the inflated central portion of the cell leaving 
empty walls above and below. The successive stages in this process 
are marked by abandoned curving layers of the thickening endospore 
(see p. 150 for description of chlamydospore formation). 
There are two principal distinctions between these spores and 
ordinary chlamydospores. The first of these is seen in the position 
of the spore in the hypha and in the character of the empty portions 
i 
