LYMAN: STUDIES OF HYMENOMYCETES. 
183 
and the position of the chambers may be nearly or quite hidden. In 
his description of this species, Morgan (’ 95 ) characterizes this veil 
as “a thick white floccose membrane, which after maturity splits 
irregularly in a radiate manner.” The term membrane is misleading, 
for it is never a separable layer, nor is it distinguished in any way 
from the tissue of the trama from which it has arisen, save that the 
hyphae may be more loosely compacted. Neither has the writer 
observed that it splits radially at maturity; on the contrary, as noted 
above, he finds that the thickness frequently increases and the pores 
become more completely hidden. 
The trama is composed of loosely interwoven hyphae, from which 
arise branches that turn outward, fork more or less in a cymose fashion, 
and form the basidia (pi. 22, fig. 106-107). The hymenium is com¬ 
posed entirely of basidia of various ages, there being no paraphyses. 
It was.thought that this peculiar fungus might show great variation 
in the character of the basidia, and perhaps possess hymenial conidia. 
This expectation was not realized, however, for the basidia are normal 
in every way, being clavate in form, and regularly 4-spored. 
The basidiospores (pi. 22, fig. 108) are hyaline, elliptic-oblong, 
apiculate, inequilateral, 2.5-3.5 p X 5-6 p, and usually contain a 
pair of refractive guttulae. In old specimens the chambers and 
passages of the hymenial stratum become filled with a mass of ma¬ 
ture spores whose free dissemination is prevented by the veil below. 
Cultivation of basidiospores .— Germination occurs in from 15 to 20 
hours in drop cultures, the spores swelling slightly, and each develop¬ 
ing a single germ tube (pi. 22, fig. 109). A primary mycelium is pro¬ 
duced with vacuolate, copiously branched hyphae, 1.5-3 p in diameter. 
After four or five days numerous chlamydospores are formed and 
growth in the drop culture is practically suspended. Only in three- 
weeks-old cell cultures possessing unusually large nutrient drops were 
any clamped hyphae of the secondary mycelium observed. However, 
if the young primary mycelium is transferred to an agar tube, the 
secondary mycelium develops in a much shorter time. Its hyphae 
are larger than those of the primary mycelium, bear numerous clamps, 
and produce chlamydospores abundantly. No oidia nor conidia were 
found upon the mycelium. Basidiosporic fructifications were pro¬ 
duced in from four to five weeks on sterilized sticks of Cephalanthus 
and other wood in jars (pi. 23, fig. 128). The development was has¬ 
tened and increased by adding a little nutrient material, particularly 
