38 BACTERIA IN RELATION TO PLANT DISEASES. 



The following final observations were made January 13, 1906: These canes, planted 

 in the fall of 1904 and inoculated May 22, 1905, grew very slowly through the first winter 

 season and were rather old and woody at the base when inoculated at the end of May. The 

 primary signs developed first on the inoculated leaves in the vicinity of the needle-pricks 

 and ran down to the stem, but secondary signs have not been visible. The canes which 

 have been inoculated 8 months are large and have been large and leafy all summer, too tall 

 in fact for the house in which they were grown. They are still quite leafy, although a good 

 many basal leaves have died. I looked repeatedly through the summer and autumn for dis- 

 tinct signs of white striping in the uninoculated leaves and could not satisfy myself that there 

 were any. Some of the labels have dropped off, and it is now hardly possible in many 

 instances to know to which cane of the row the label belonged. 



I cut out the inoculated rows first and dissected all of the canes, dictating results to 

 the stenographer from time to time as I cut and made examinations under the hand-lens : 



Cinta. 



First row to the north (inoculated row) : 



Removed a large stem, which is leafy to the base. Find it sound within. From its soft texture 

 it is probably a younger shoot which has developed since the date of the inoculations. Split the base 

 carefully and examined for presence of yellow stain or red stain in the stem ; there is none. 



Removed another stem, basal leaves of which are dead. It has not reached nearly the diameter 

 of the preceding. It appears to be an older stem. The top looks sound, and there are no indications 

 of disease in the stem. 



Neither of these canes had any label on them. 



Removed a cane that is labeled 626. It is a large old cane which has lost its leaves nearly to the 

 top. As before remarked, I do not have much confidence in the labels now being on the particular 

 canes which were inoculated, since in some instances at least the gardeners picked up fallen labels 

 and wired them to any convenient place. No disease in the upper part of the cane. Cross-sectioned 

 every internode; no disease in any part of the cane. 



Large leafy cane, upper part of which is quite soft, showing that it has grown since the date of the 

 inoculation. Sound within. No recent sprouts from the base of this clump. 



Next clump : Removed 2 young sprouts which may be about 6 feet high. They are both sound 

 at the base, and also further up. These have grown within the last 2 or 3 months. 



A very large cane ; extremely thrifty leaves, except the basal ones, which are dead. This also is 

 a cane which has grown since the sprouts were inoculated. Tissue soft and immature (in the lower 

 part). Perfectly sound. 



There remain in this clump 2 old canes; these are leafy at the top, leafless for the lower 4 feet or 

 so. Stems small, firm. First cane sound in the upper part; also in all other parts. No yellow slime 

 in the vessels, and no red stain. The second old cane is like the first, but has lost more leaves. It is 

 leafless to a height of 6 feet. Top part sound. In the basal part I find a brown stain in one group of 

 vessels, which, however, is very slight, and soon runs out. 



Third clump on this row : Label 630. This is a cane dating from the time of inoculation. It is 

 leafless for a height of 6 feet. It is sound at the top. It has red bundles in the stem at the base. 

 There are a dozen or fifteen of these. The stain in the vessels disappears 15 inches higher up. There 

 is no reasonable doubt that the inoculation has taken slightly in this stem. The staining seems to be 

 most extensive in the vicinity of the basal half dozen nodes. The cane is sound externally. Under 

 the hand-lens I see bacterial ooze from some of the red-stained vessels. On splitting the stem some 

 portions of the bundles are seen to be red and other portions to be pale yellow, the stain being irre- 

 gularly distributed in them, just as it was in the set of canes previously inoculated. 



This third clump has quite a number of young shoots coming out of the ground. These are 

 sound at the base. 



Old cane. It dates from the time of inoculation and is leafless for a distance of 6 feet. Sound 

 throughout. 



Old cane, leafless for a height of 6 feet. Sound throughout. 



A large cane, leafless for the first 4 feet. Very green above. Upper part sound. Middle por- 

 tion rather undeveloped. Cane has probably grown since the last inoculation. Basal part sound. 

 All the rest sound. 



The next clump, same row : Young shoot. Sound at base and all the rest of the way. 



Old shoot, leafless for a distance of 5 feet. Whole cane sound. 



These canes are purple-striped. 



