42 BACTERIA IN RELATION TO PLANT DISEASES. 



frosted somewhat before the house was shut, i. e., it projected through the ventilators. The rot 

 ceases suddenly at a distance of about 7 feet from the ground, and the rest of the way the stem is 

 entirely sound. 



Remark. This ends the first (north row) of the Louisiana No. 74. There are no indi- 

 cations of bacterial disease in it beyond the very slight ones mentioned under particular 

 canes. 



On January 19, examination of the inoculated cane was continued, as follows: 



Common Green. 



North (inoculated) row: 



Six young shoots from the base in a rather unhealthy condition ; height 2 to 3 feet. The leaves 

 are not white-striped, but many of them are dead on the margins. 



1. Center dead. No red or yellow stain in the bundles. 



2. Center dead. No red or yellow stain in the bundles. 



3. Two middle leaves dead. Brown, water-soaked. No sign of the gum-disease. 



4. Outer leaves dead. Center of the stem sound. Further up the terminal bud is dead and soft- 

 rotted, but there are no signs of the yellow gum-disease. 



5. Central bud rotted out. I see no evidence of Cobb's disease. 



6. A few red bundles at the extreme base. Further up the whole stem is dead and soft-rotted ; 

 not Cobb's disease; it seems to be a brown soft rot which has run in from the terminal bud. 



Old large cane. This bears label 830. All the lower leaves are dead, that is, up to a height of 8 

 feet. Sound at the base. Sound at the top on cross-section; continues sound on cross-section for 

 many feet. The only evidence of disease in the vascular system is about a foot from the ground and 

 confined to one node, a bundle of which is stained brownish, and to another node about 6 inches lower, 

 where there is a red-stained bundle ; that is, disease absent or extremely slight. No internodal stains, 

 so far as I can see. 



Another old stem. Sound at the base. Basal buds well developed. Very leafy and green for 

 many feet. It is undoubtedly a shoot which grew after the date of inoculation. Sound at the top on 

 cross-section, and throughout. 



Young shoot from the next clump. Heart rotted out. No evidence of yellow bacterial ooze in 

 this stem. 



Another young shoot. Heart rotted out in the same way. 



Old shoot, very tall. Leafless for the first 6 feet. Upper part of the shoot has sound, green 

 leaves. The length of this cane is about 10 feet (that is, of the stem itself). On cross-section not a 

 trace of disease either in the nodes or internodes. 



Another old cane. This bears label No. 846. All of the leaves are dead, except a few at the top. 

 It is a large cane, and mature for a distance of at least 8 feet. Cross-sectioned each internode from 

 the top downward. Cane sound for many feet. Basal buds well developed. At about a foot from 

 the ground there is one internodal bundle stained red-yellow, and the node below has several vessels 

 in it which are stained red and yellow. Signs of disease very slight indeed. They seem to be re- 

 stricted to this node and internode, and are scarcely worth mentioning. 



Large ripe old stem. It bears label 85 a. It is sound at the base. The basal buds are well devel- 

 oped. The leaves are dead nearly to the top. It is a tall cane, and sound externally. Cross- 

 sectioned from the top downward. No signs of disease anywhere. 



Old stem. Sound at the base. Basal buds well developed. Leafless except for a few green 

 leaves at the top. Cross-sectioned from the top downward in every node : No signs of disease in any 

 part of the cane. 



Old cane. Sound at the base. Basal buds well developed. Stem sound externally. Leafy 

 toward the top, leaves healthy looking. Cross-sectioned : Interior of the stem healthy throughout. 



Healthy young shoot, about 5 feet high. Stem sound on cross-section. 



Old cane, leafless nearly to the top. Sound at the base. Basal buds well developed. This 

 bears label 866. The diameter of this cane is about i .5 inches. On cross-section, one or two red ves- 

 sels in the stem 6 feet from the ground ; these soon run out to appear again a little lower down ; they 

 extend through several nodes, and a larger number appear at a level of about 3 feet, but are not 

 numerous even there. General appearance of the stem is good. Red stain runs out again a little 

 lower down. Basal 2 feet of the stem entirely sound. Laid aside a piece of this stem to see if there 

 would be any bacterial ooze. 



Cane about 8 feet high, evidently developed since the inoculation. Sound externally and within. 



Old cane, quite leafy at the top, naked below. Basal buds well developed. Sound at the base 

 and within its whole length. 



