F. T. Brooks and M. A. Bailey 199 



(3) A standard Czar, 3-4 years old, treated as in (1) but the cut 

 surface was covered with Stockholm tar. On May 13th, 1914, a branch 

 4| inches below the cut end was silvered although a branch three inches 

 nearer was normal. Silvering did not progress further during the 

 summer. 



(4) A standard Czar, 3-4 years old, treated as in (1) but the cut 

 surface was made smooth with a knife and left exposed until inoculation. 

 On May 13th, 1914, silvering was evident on a branch IJ inches below 

 the cut surface which was gumming. Silvering spread during the summer 

 until nearly the whole tree was aiJected. 



(5) A standard Czar, 3-4 years old, was cut back with a saw 

 December 2nd, 1913, and left untreated. Inoculation with sporophore 

 material of the same gathering was not performed until March 2nd, the 

 fungus being removed and the tube replaced the following day. This 

 tree remained unsilvered. 



(6) As in (5) but the cut surface was covered with gas tai-. The 

 tree remained unsilvered. 



(7) As in (5) but the cut surface was covered with Stockholm tar. 

 The tree remained unsilvered. 



(8) On December 13th, 1914, the main stem of a standard Victoria 

 tree 3-4 years old, was cut back with a saw, under sterile conditions, to 

 within two feet six inches from the ground, and the cut surface was 

 immediately covered with a sterile tube embedded in a collai- of plas- 

 ticine. A sporophore of the same gathering as before was inserted on 

 March 2nd, 1914, and was removed the following day, the tube being 

 replaced. In this experiment and in the next two, the inoculations 

 were carried out under conditions as sterile as possible. On May 13th 

 silvering was apparent in two branches eleven and eighteen inches 

 respectively from the cut surface which was gumming. Other branches 

 nearer the cut surface but with a different orientation were unsilvered 

 and remained so throughout the summer. 



(9) As in (8) except that the cut surface of the main stem was made 

 smooth with a sterile knife. On May 13th two branches about eight 

 inches below the cut surface were silvered, although two branches 

 nearer the top were normal. By the first week of June all branches 

 showed some silvering which became more marked as the season 

 advanced. 



(10) As in (8) except that the upper part of the main stem was half 

 sawn, half broken across. On May 13th some of the leaves on the upper- 

 most branch arising six inches below the cut surface were silvered, like- 



