Stigar-Cane in the West Indies. 405 
part of the stem, in a resting condition, where it can be seen 
as a white felted mass on the scale-leaves of the buds. 
When, however, the canes are cut in March, and the closely 
packed condition of the soil combined with extreme dryness 
prevents anything like rapid growth of the buds at the base 
of the cane-stumps, the mycelium, after luxuriating in the rich 
substratum afforded by these stumps, is able to assert itself 
and master the young shoots, and thus make up for the long 
period of waiting. As the new shoots develop with great 
slowness during the dry season, the fungus has time to destroy 
most of the roots at the base, at the beginning of their 
development, and thus to give rise to the dwarfed canes so 
characteristic of the second crop of the lowlands. When the 
rains come, only a few roots are available for the supply 
of water and minerals, and, in spite of the liberal application 
of artificial manures, practically no growth results. 
The fact that the fungus is not so destructive to rattoon 
canes on the red soils of the highland districts as to those on 
the black soils of the lowlands, seems to be largely due to the 
much greater rainfall during the dry season in the former 
districts than in the latter. 
We can to a great extent regard the first and second crops 
of canes on the lowland districts of Barbados as infection 
experiments on a large scale with the fungus Marasmius . In 
the case of the first crop, conditions favour the cane and there 
is little disease. In the second crop, everything helps the 
fungus and at the same time checks the host, consequently 
a root disease, epidemic in character, often results. Further- 
more, it is caused by a fungus which, under ordinary circum- 
stances, can do little damage to the cane, but which, when 
conditions are against the host, can become a parasite and 
even overcome meristemmatic tissue such as that at the 
growing-point of the cane-root. 
We have, therefore, a striking example of the influence of 
the environment on the result of the struggle between the host 
and the parasite, and a confirmation of the views brought 
forward on this subject by Marshall Ward (2). 
