LYMAN: STUDIES OF HYMENOMYCETES. 
169 
finally appear at practically all septa even out to the extremities of 
the hyphae. All subsequent growth is fully provided with clamps. 
Reproduction in cultures .— No indication of spore formation of any 
kind was observed in drop cultures of either basidiospores or conidia, 
although various media were used and the cultures were kept for 
weeks until the hyphae lost their contents. Nutrient-agar tubes, 
also, usually produced only a sparse growth of sterile mycelia, although 
in rare instances a few sporodochia were formed on hard potato-agar. 
No oidia or chlamydospores were seen in any culture of this fungus. 
In cultures on sticks of Alnus or Salix in jars and large test tubes, 
Aegerita sporodochia were produced in abundance. There was no 
difference observable between a culture originating from the germina¬ 
tion of a basidiospore and one from a conidium, save the temporary 
distinction that the latter was usually a little more tardy in beginning 
the formation of sporodochia. The first sporodochium was observed 
after four to five weeks, from which time the formation increased 
steadily until, at the end of three months, the production in many 
cultures was equal to the most abundant ever found in the field. 
Portions of the stick were whitened by the sporodochia, and even the 
sides of the vessel over which the mycelium had spread were thickly 
dotted with them (pi. 26, fig. 138). Moreover, an elementary forma¬ 
tion of basidiosporic hymenium made its appearance after three or 
four months in all the wood cultures started from basidiospores, and 
in some, although not all of those started from conidia. 
Thus the complete life history has been followed in pure cultures 
beginning with both the basidiospore and the conidium; and the 
connection between the Peniophora and the Aegerita is conclusively 
shown by the appearance of both types of fructification in the same 
culture, whether the starting point be the basidiospore or the conidium. 
Development of the sporodochium .— Inasmuch as only sterile 
mycelia were produced in drop cultures, it was not possible with the 
microscope to follow a single sporodochium through all stages of its 
development. The process is easily understood, however, from the 
study of wood cultures in large test tubes. In the latter the mycelium 
soon spreads from the wood over the sides of the tube and forms a 
copiously branched, anastomosing network (pi. 26, fig. 138). A 
portion of this network scraped off and mounted on a slide shows 
young sporodochia in all stages of development. 
The first step in the process is the formation, near the end of a hypha, 
