VIII, c, 
Broivn and Graff: Fungus Succession 
25 
racemosa; 3, A. caerulea and Oospora sp. ; 4, A. caerulea and 
Coprinus stercorianus ; 5, A. caerulea and Coprinus plicatilis; 6, 
all five of the fungi mentioned above. 
The growth in the unsterilized checks was quite similar to 
that in the unsterilized cultures previously described. There 
was a growth of mucors followed by Oospora and this in turn by 
Coprini. The growth of the mucors and Oospora was very 
scanty and disappeared in less than ten days. 
The mucors and Coprini, with whicih the sterile dung was in- 
oculated, commenced to grow immediately and in three days 
there was a vigorous growth of both. The growth of Oospora 
was not visible as soon as that of the other fungi, owing prob- 
ably to its small size. The mucors reached their maximum 
development in five, and the Coprini in ten days. The growth 
of the individual fungi was in every case much greater than in 
any unsterilized check, while the total growth on the sterilized 
was always many times greater than on the unsterilized dung. 
There were so few hyphae in the unsterilized dung that they 
might easily have been overlooked on superficial examination, 
while in the sterilized they were so abundant that a compact 
felt was produced. In the fiasks containing the Coprini this 
was so dense even after drying that water poured on the surface 
of the felt did not penetrate into the interior. All of the fungi 
moreover remained alive until after the substratum had appar- 
ently become air dry. Since Absidia caerulea grew very much 
better when grown on sterilized dung with any of all of the 
other fungi than it did in any of the unsterilized checks, and 
showed no signs of dying except with the drying out of the 
substratum, it would seem that neither any nor all of these fungi 
could have produced the deleterious effect observed. The vigor- 
ous growth of Mucor racemosa with all of the other fungi would 
indicate that the same thing was true in the case of this species, 
while the vigorous growth of the Coprini would, likewise,, seem 
to show that the sterilization of the substratum was favorable 
to the vegetative development of these. They, however, pro- 
duced very few fruit bodies, which would seem to be due to the 
vigorous growth of the, hyphae having exhausted the substratum 
of food or moisture, before reaching the fruiting stage. 
The growth of Absidia caerulea on the sterilized substratum 
appeared to be inversely proportional to that of the other fungi. 
It ferew best when alone ; next with Oospora which is a small and 
slow growing fungus; and poorest when with all of the other 
four fungi. Mucor racemosa is a much larger and more rapidly 
