IIOTSON. — CULTUKK STl'DIKS OF FUNGI. 295 



diameter nearly equal to that ot" the l)iill)il itself and eomjxjsed of 

 interlaeing h\ i)hal strands, whicli arc paitly made up of branches from 

 the procumbent hyphae and partly by the branching of the original 

 \-ertical ones. These sui)ports or "stalk-like" structures \ary in 

 length, some being ((uite long (100 /jl), while at other times the bulbils 

 appear to be almost sessile on the horizontal branches. The primor- 

 dia that are produced later, are hindered in their upward growth by 

 the presence of the first formed bull)ils, which, however, are soon 

 broken away from their attachments and pushed up so that eventually 

 se\eral irregular layers of independent spherical bodies arc produced, 

 the oldest ones being on the surface. Whether the vertical hyphae 

 first formed fuse at the apex could not be determined. They evidently 

 receive some stimulus, for they begin to send out short branches in 

 different directions, Avhich in turn divide and subdivide, and these 

 intertwine among themselves and, with other hyphae that grow up 

 from the original horizontal branches, form an interlacing weft which 

 becomes more and more compact, producing a hyaline, spherical body 

 in which the walls are very thin and almost indistinguishable except 

 after staining. As they increase in size they assume a brownish tint 

 and finally a rich tan-color, during which time the walls gradually 

 become more definite and eventually are well marked. 



Since liquid media appeared to have a peculiar aft'ect on the develop- 

 ment of these bulbils, cultures W'cre tried in large flasks on pieces of 

 wood partly immersed in bran decoction, so that the effect of different 

 degrees of moisture might be observed, as the mycelium spread from 

 the liquid medium toward the dryer portions of the wood. Under 

 these conditions it was found that the bulbils formed on the wood 

 about three or four inches above the liquid, began to assume a paler 

 aspect and soon became light straws-colored, instead of the dark tan of 

 the normal bulbil. On examination it was found that the cells com- 

 posing these pale bulbils, instead of being compact with angular walls 

 as in the normal form, had rounded up and become spherical (17-22 f^ 

 in diameter), adhering very loosely by means of a nmcilaginous mate- 

 rial that had evidently been secreted by them, so that a very slight 

 pressure w^ould separate them into in<li\'idual spores (Figure 8, 

 Plate 11). The germination of these "spore-masses" w^as followed 

 carefully in Van Tieghem cells — -some crushed, others not — and it 

 was found that nearly all the spores germinated in twenty-four hours, 

 some producing one, others two germ tubes, w'hich were hyaline and 

 septate, becoming much branched (Figures 9-10, Plate 11). When 

 allowed to remain adherent, the spore-mass sent out germ tubes in all 



