CONTRIBUTIONS FROM THE WISLEY LABORATORY. 71 
Hydrochloric 
acid 
n 
Nitric acid 
Sulphuric acid 
Chromic acid 
Potassium bi- 
chromate 
Strength of 
Solution. 
i per cent 
» » 
1 per cent. 
»» 
>> 
> > 
1 per cent. 
>> 
>> 
\ per cent. 
>> 
11 
>> 
1 per cent. 
Period of 
Soaking. 
72 hrs. 
96 „ 
18 „ 
24 „ 
48 „ 
"72 „ 
96 „ 
18 „ 
24 » 
48 „ 
72 „ 
96 „ 
18 „ 
24 99 
48 „ 
72 „ 
96 „ 
18 „ 
24 „ 
48 „ 
72 „ 
96 „ 
Effect on Growth of 
Healthy Bulb. 
slightly damaged 
damaged 
no injurious effect 
very slightly 
damaged 
slightly damaged 
damaged 
badly damaged 
very badly 
damaged 
bulbs killed 
growth dwarfed 
slightly damaged 
»> 
growth dwarfed 
very slightly 
damaged 
»» 
damaged 
badly damaged 
Condition of Eelworms 
in Bulbs. 
live eelworms 
found 
The experiments were duplicated in Lincolnshire and in all cases the results 
coincided with those obtained at Wisley. 
To test the extent a solution was capable of penetrating the 
bulb, a 1 per cent, solution of eosin was employed in which the bulbs 
were soaked. On examining the bulbs at intervals of 18, 24, 48, 
72, and 96 hours respectively it was observed that the solution had 
not even passed through the outer scales of the bulb, whereas the 
base had absorbed the liquid fairly readily. We are thus able 
to account for the damage caused to the healthy bulbs by such 
solutions as copper sulphate, mercuric bichloride, &c. The solution 
gained an entrance via the basal plate, the tissue of which had been 
so injured as to prevent healthy root growth. All the bulbs on which 
the solutions had acted injuriously had failed to produce sufficient 
roots and in some cases no roots were emitted. While it was 
possible to kill a healthy bulb by soaking in a chemical solution, live 
eelworms were to be found inside a diseased bulb treated in the same 
manner. The percentage of eelworms killed by the soaking was not 
considered, because untreated diseased bulbs always contain a number 
of dead eelworms. In treated diseased bulbs the question would arise 
as to how many of the dead eelworms were killed by the solution, and 
how many had died a natural death. The fact that live eelworms 
were found in a treated diseased bulb suffices to show that the 
treatment was inadequate. 
In no case was soaking in cold solutions of chemicals of any avail, 
and no recommendation as to their use can be made. 
