40 BACTERIA IN RELATION TO PLANT DISEASES. 



As noted the other day, the labels are lost in many cases, and we can not tell whether this was an 

 inoculated cane or not. 



Next clump: Young shoot, very leafy and green. Sound within. 



An old shoot. Sound at the base. Cane destitute of leaves for the first 9 feet. Sound within 

 at the top; sound all the way down. 



Next clump: Small old cane. Sound at the base. Stem naked for the first 8 feet. Leaves 

 above not striped. Terminal bud sound. Stem sound within all the way down. 



Another old cane. Three red bundles at the base on cross-section. Stem naked nearly to the 

 top. No white striping of the foliage. The gardener topped this cane some weeks ago in order to 

 shut the ventilators of the house; the result is that there are purple-red bundles under this topped 

 part for a distance of about a foot down. Six inches under they are 40 in number; 6 inches further 

 they are reduced to 3 in number; below the next node they are reduced to 1 ; under the next node this 

 one disappears. These are clearly due to topping the cane. The cane from this point is sound down- 

 ward for many feet, until within a few inches of the ground (the last 5 or 6 nodes). In these there 

 are a few bundles stained yellowish-red, and from these on cross-section there is a slight yellow bac- 

 terial ooze. 



Another old cane: Sound at the base, except that there are three red-stained bundles. Desti- 

 tute of leaves for the first 4 feet ; leafy the rest of the way, but some of the leaves dead on one margin. 

 No distinct white striping. Sound at the top on cross-section, and for many feet, that is, down to 

 the extreme base. 



Another clump: Two young shoots about 6 feet high. Very leafy, sound within. 



Old shoot. Very woody at the base and hard to cut. Stem much larger 2 feet above the base. 

 Buds pushing slowly. Naked the first 4 feet; very leafy the rest of the way. No external signs of 

 disease. Cross-sectioned from the top downward. Sound at the top; continues so for many feet, 

 that is, entirely to the ground. 



Old cane. Destitute of leaves for the first 6 feet. Sound at the top on cross-section, and all the 

 way down. 



Another old cane. Nearly destitute of leaves. Sound at the top on cross-section; continues 

 sound for many feet. No indications of disease anywhere in the interior of the stem. 



The remark about labels remains in force, that is, they have fallen off in most cases. 



Another old stem leafless for many feet. Sound at the base. Top leaves not white-striped; 

 terminal bud dead. Sound under the terminal bud. Stem continues to be sound on cross-section 

 for a distance of many feet down. First sign of red bundles about 6 inches from the ground. These 

 are very few in number and soon run out. No signs of any yellowing of the vessels, or of bacterial 

 ooze. 



Another old stem; leafless nearly the whole length. Sound at the ground; also at the top and 

 for many feet down. I find no red stain or yellow slime anywhere in the vascular system. 



Another old stem; leafless nearly the whole length. Sound at the ground, with the exception of 

 a red stain in one or two bundles. Upper leaves not white-striped. Sound within at the top; con- 

 tinues sound for many feet. No evidence of disease in any part. 



Young shoot. Dwarfed and tough at the ground, expanded above. Very leafy at the top. 

 Sound externally; sound within. 



Another clump. Young shoot. About 6 feet high. Very leafy. Sound externally. Sound 

 within. 



Old shoot. Sound at the base. Leafless nearly to the top. Upper leaves not white-striped. 

 Terminal bud dead. Sound just under the terminal bud. Stem continues sound for many feet. 

 The only signs of disease are near the ground, where there are a few red bundles beginning in one of 

 the nodes. 



Old cane. Sound at the ground. Leafless for 6 feet. Upper leaves not white-striped. Cross- 

 sectioned from top downward; sound within all the way down. 



Another old cane, last one of this row. Sound at the base. Leafless for many feet. Upper 

 leaves not white-striped. Sound at the top on cross-section. Continues sound all the way down, 

 except in one node and internode near the base, where there are a few reddened bundles, and very 

 slight evidence of bacterial occupation. 



Genual Remark on this Variety. There is no doubt whatever that the bacteria entered 

 the stem in some of these plants, but they were not able to make their way through these 

 stems so as to induce any general disease. If one did not know that they had been inocu- 

 lated and did not search critically for the presence of the red bundles and the bacterial ooze, 

 he would never suspect that anything had been done to the canes. 



