206 Transactions British Mycological Society. 
veloped fruit-bodies one day before the first monosporous 
mycelium. Although all the eleven dung cultures produced 
rudimentary fruit-bodies, in only six of them did the rudiments 
continue their development to maturity. This, however, appeared 
to be due to the conditions of nutrition, aeration, transpiration, 
etc.; for, when transfers were made to large masses of sterilised 
dung contained in crystallising dishes, fruit-bodies were produced 
which elongated their stipes, expanded their pilei, and shed 
spores in the normal manner (Plate VII, Fig. 2). 
Later, an eleventh monosporous mycelium was removed from 
a dung-agar plate and placed directly in a large crystallising 
dish of horse-dung which had been sterilised by heating on 
three successive days. This culture showed very little surface 
mycelium but eventually produced several large normal fruit- 
bodies. 
All the fruit-bodies produced in the monosporous and the 
bisporous agar-tube and dung-tube cultures were imperfect, 7.e. 
their pilei produced no ripe spores and, at maturity, were, 
therefore, white or pale yellow instead of being grey. However, 
when monosporous mycelia were transferred from the tubes to 
sterilised horse-dung contained in large crystallising dishes, they 
produced many perfect spore-bearing fruit-bodies, as well as 
some which produced many spores which never ripened, very 
few ripe spores, or no spores at all. This imperfection of certain 
of the fruit-bodies in each large pure culture, in respect to 
spore-production, was observed not only in all the monosporous 
cultures, but also in all the polysporous cultures. Altogether 
seventeen cultures exhibited imperfect spore-production and, 
of these, ten were monosporous in origin and seven polysporous. 
Since the fruit-bodies of both monosporous and polysporous 
pure cultures behave in the same manner as regards imper- 
fection of spore-production, this phenomenon cannot be due 
to the haploid or diploid condition of the mycelium but must 
be due to some other cause, such as the over-production of 
fruit-bodies of large size or to the absence from the nutrient 
medium of certain chemical compounds which in unsterilised 
dung are ordinarily produced by associating and competing 
organisms. 
A wild fruit-body of Coprinus lagopus came up on horse-dung 
taken from a stable, and it shed spores which were collected as 
a spore-deposit. Some of the spores were plated out on agar and 
thus a monosporous mycelium was obtained. This mycelium 
was transferred to sterilised horse-dung in a large crystallising 
dish. Here it fruited nineteen days after the spore from which 
it originated had been sown. From this second fruit-body a 
second monosporous mycelium was obtained which also fruited. 
