494 BOTANICAL GAZETTE [JUNE 
only verified what little was known, but has been able to cultivate the fungus 
and trace its life history, neither of whichhad been done before, and to supply 
some details of its action on the horn. 
The principal new points concern the development of the sporophores, 
which arise as domed or club-shaped masses of hyphz and stand up into the 
air covered with a glistening white powder. Closer investigation shows this 
to consist of chlamydospores, formed at the free ends of the up-growing 
hyphe. Their details of structure and development are fully described, and | 
their spore nature proved by culture in hanging drops. The germination, 
growth into mycelia, and peculiar biology of these hitherto unknown 
spores were followed in detail, and in some cases new crops of chlamydospores 
obtained direct in the cultures. 
When the crop of chlamydospores on the outside of the young sporo- 
phore is exhausted, the hyphz which bore the spores fuse to form the peridium 
clothing the head of the sporocarp, and peculiar changes begin in the internal 
hyphe below. 
Minute tufts or knots of claw-like filaments spring from the hyphe 
forming the main mass of the fungus, push their way in between the 
latter, and so find room in the mesh-like cavities. Here the closely 
segmented claws form asci-—they are the ascogenous hyphz—and 
the details of development of the asci, their nucleated contents, and the 
spores are determined. As the spores ripen, the asci, which are extremely 
evanescent, disappear, and in the ripe sporocarp only spores can be seen 
ying loose in the meshes of the gleba. The ascomycetous character of 
the fungus is thus put beyond question, though the peculiar behavior 
of the developing ascogenous tufts at one time rendered it questionable 
whether the older views as to the relationships were not more probable. 
No one had hitherto been able to trace the germination of these ascospores 
—the only spores known previously—and De Bary expressly stated his 
failure todo it. The author finds that they require digesting in gastric juice, 
and so in nature they have to pass through the stomach of the animal. 
using artificial gastric juice, and employing glue and other products of 
hydrolysis of horn, the details of germination and growth into mycelia, 
capable of infecting horn, were traced step by step under the microscope 
and fully described. 
No trace of any morphological structure comparable to sexual organs 
could be discovered, though many points suggest the alliance of this fungus 
with Erysiphez and truffles. 
The author also found that similar digestion promotes the germination of 
the chlamydospores, and in both cases has not only traced the germination 
step by step, but has made measurements of the growth of the mycelium, 
induced the formation of chlamydospores on the ra ica again, and 
