oct. 2,1916 Effect of Blackyot Fungus on the Apple 37 
A further comparison of the alcohol content of sterile tissues and the 
artificially inoculated material was made. Forty-gm. samples of pulp 
prepared and sterilized as usual and incubated for 30 days after inocula¬ 
tion of half the number of flasks were employed. Two hundred c. c. of 
water were added to each flask and distillation continued until alcohol 
ceased to come over and 50 c. c. of distillate had been collected, when 5 
c. c. samples were titrated. These distillates are two-fifths as strong as 
those obtained from the fresh material, when amounts of pulp and dis¬ 
tillate are compared. When corrections are made for this difference, the 
results for the check and the inoculated material are for 5 c. c. of distil¬ 
late, 7.5 and 10.5 c. c., respectively. 
The experiments agree in showing that there is a considerable increase 
in the alcohol content of tissues invaded by the blackrot fungus, whether 
under natural or artificial conditions; moreover, they show that this 
increase proceeds at an equal pace with the disappearance of soluble 
carbohydrates from the affected fruits. 
SUMMARY 
A quantitative analytical comparison of the chemical composition of 
normal mature Red Astrachan apples with that of similar fruits in two 
stages of decay as a result of attack by Sphaeropsis malorum reveals cer¬ 
tain well-marked alterations in composition which proceed at an equal 
pace with the progress of the disease. 
(1) The loss of water from the affected tissues is small, amounting to 
4.61 per cent of the original weight in the case of fruits which had just 
reached the stage of complete decay. 
(2) There is a very considerable reduction in the total solids present, 
amounting to 6.80 per cent in totally decayed fruits. 
(3) There is a very marked reduction, concurrently with the progress 
of the disease, in the amount of the constituents removed by successive 
extractions of the pulp with alcohol, ether, water, and alcohol. In sound 
fruit these make up 78.94 per cent of the total solids, in wholly decayed 
fruits 65.14 per cent. This reduction goes on very slowly in the earlier 
stages of the disease but quite rapidly in the later stages. 
(4) There is a decrease, followed by an increase, in absolute as well 
as in relative amount of lipoid constituents extracted by alcohol or ether, 
and precipitated from watery emulsion by chloroform, with the progress 
of the disease. In half-decayed material these constituents are reduced 
to 83.17 per cent of the absolute amount found in sound fruits; in wholly 
decayed material they are increased to 121.48 per cent of the total content 
of the sound apples. In the onset of the disease there is active attack and 
transformation of the lipoid constituents of the host; later there is rapid 
construction of lipoid materials by the parasite. 
(5) The nitrogen extracted by alcohol, water, and ether, which rep¬ 
resents the nitrogen of proteoses, peptones, polypeptids, amino acids, 
and nitrogen bases, steadily decreases with the progress of the disease, as 
