Summary 
fungus present in infected seed may be destroyed by use of this machine. 
In this machine, the effective treatment for control of the disease with¬ 
out serious diminution of germinability consists of 20 to 24 hours of 
desiccation at 60-65° C. followed by 12 hours of heating at 95-100° C. 
14. The moisture content of cotton seeds is a factor which strongly 
modifies their resistance to heat and which may be used as a criterion 
of their ability to withstand the temperatures that are effective in the 
control of anthracnose. Without exception, when the moisture content 
after the preliminary drying was as great as 3.9 per cent of the oven 
dry weight, the viability of the seeds was seriously impaired by heating 
at 95° for 12 hours. When the moisture content after the preliminary 
drying was not greater than 3.62 per cent of the dry weight of the seeds, 
no serious loss of viability resulted from the treatment at 95°. 
15. When the water content after drying was not greater than 3.19 
per cent of their dry w r eight, the seeds heated at 95° for 12 hours germi¬ 
nated more promptly than the untreated seeds used for a check. This 
accelerated germination is not due to any wholesome effect of the treat¬ 
ment on the embryo of the seed, but is to be attributed to changes 
in the seed coat which facilitate access of water to the embryo. Naked 
embryos from treated seed germinate somewhat less promptly than 
treated embryos, but when seeds are germinated with coats intact, this 
effect is completely masked and amended by the favorable changes in 
the seed coat. 
16. The viability of the seed-borne elements of the anthracnose 
fungus w T as prolonged by storing infected seed over such desiccating 
chemicals as concentrated H 2 S0 4 and CaO. This result shows that the 
death of the anthracnose fungus when infected seeds are treated with 
dry heat is not due to the desiccation accompanying the treatment but 
to a more direct effect of the heat on the fungus protoplasm. The 
necessary preliminary desiccation serves only to prepare the seeds to 
endure the high temperature used in the final stage of the treatment. 
17. The thorough desiccation which occurs when cotton seeds are 
stored for long periods over concentrated H2SO4 and dry CaO, induces 
a condition of more or less complete secondary dormancy in many of the 
seeds. This condition is slowly reversible and is characterized by a very 
hard and dry condition of the seed coat which prevents absorption of 
water. The embryos of such seed germinate promptly upon removal 
of the seed coat. 
18. The storage of infected cotton seed in hydrogen and carbon 
dioxide does not free the seeds from anthracnose. 
