32 BACTERIA IN RELATION TO PLANT DISEASES. 



ation of the tissue does not extend for more than o. 1 25 inch either way from the needle-pricks. There 

 is no sign that the inoculation has been effective. 



No. 45*. This is an excellent cane, being about 9 feet long and 1.25 inches in diameter. The 

 lower internodes are about 6 inches long, while some of the upper ones are at least 8 inches in length. 

 The whole stem, with the exception of the inoculated internode, is perfectly white within, there 

 being no discolored bundles. In the inoculated internode a red discoloration has extended in one or 

 two cases about an inch from the needle-pricks. There is no sign of a general infection, however. 



Check. The stem containing the check-pricks is rather small, as it has been crowded by the 

 larger canes in the stool. There are no discolored bundles, however. The needle-pricks present 

 much the same appearance as they did in canes Nos. 44, 45, etc. 



No. 46. This is a small cane, about 4 feet in length and 0.75 inch in diameter. It has not made 

 much growth. Some of the leaf-sheaths in the upper part of the stem are brown and dead. The 

 terminal bud seems to be healthy. There are very many discolored bundles, however, in all the leaf- 

 sheaths which envelop the bud, and in the upper part of the stem much of the vascular system is dis- 

 colored, there being at least 100 red and yellow bundles. The portion of the stem below the inoc- 

 ulated internode, however, seems to be perfectly white, the infection having run up rather than down 

 the stem. There seems to be a little yellow ooze from many of the bundles in an internode which is 

 at least 4 feet above the one inoculated. This cane was taken to the laboratory for microscopic 

 examination. 



LABORATORY NOTE. This stem shows abundant bacterial ooze in the ninth internode above the 

 point of inoculation. It comes from at least 100 bundles. Plates were poured from this stem. 



No. 47. This is a very small, stunted cane. It has made scarcely any growth since it was inoc- 

 ulated. The basal leaves are dead, but the upper ones are green and seem to be perfectly healthy. 

 There are five or six discolored bundles in the basal part of the stem. In the upper part of the stem 

 there are at least 20 discolored bundles. Thiscanehasverylittlejuiceinit. It seems to have entirely 

 dried up. 



Common Green, f 



No. 48. This is a very small and stunted plant. The terminal bud and terminal leaflets are 

 dead and shriveled. The basal three or four leaves are green along the midrib, but the leaf -sheath 

 and edges of the leaves are dead. The cane has made scarcely any growth since it was inoculated. 

 In the basal internode there are ten or fifteen yellow bundles. In the uppermost internodes the num- 

 ber of discolored bundles has increased. Whether or not the condition of this stem is due to bacterial 

 infection is uncertain, for there seems to be no yellow ooze.t The terminal bud seems to have been 

 killed from some external cause rather than an internal one. 



No. 49. This cane is quite short, being about 3 feet in height. It is very thick at the base, 

 however. The terminal bud is entirely dead and the surrounding leaflets brown and dried up. The 

 basal internodes are very short, some of them being not more than an inch in length. The tissue 

 throughout, however, is white, except in the inoculated internode and the one immediately above it. 

 In the latter there is one red bundle, which extends throughout its entire length. There is quite a 

 little discoloration within the inoculated internode, but it has not spread far in either direction from 

 the needle-pricks. There are no cavities in this internode. The tissue seems to be intact throughout. 

 A few of the bundles are discolored for two or three inches. This is the only sign of infection. 



No. 50. This is a very long cane, being about 9 feet in height. Many of the basal leaves are 

 brown, while some of the upper ones are dying at the tips and along the margins. The topmost 

 leaves have been crushed by the ventilating apparatus. The terminal bud is dead and dried up. 

 The cane at the base is about 1.5 inches in diameter and externally seems to be very heal thy through- 

 out its entire length. The only discoloration in the tissues of the stem occurs in the inoculated inter- 

 node and the two adjacent ones. Other than this, the cane is perfectly healthy. The central part 

 of the tissue in the inoculated internode has a water-soaked appearance and contains one or two red 

 bundles. 



LABORATORY NOTE. A few of the bundles in the first internodes above and below the point of 

 inoculation show the presence of bacteria. In two of them, little yellow cirri about 0.25 inch long 

 have been pushed out, and these, when examined microscopically, were found to be made up of a 

 solid mass of bacteria. 



No. 51. This is another long cane, which has made an exceptionally good growth. Some of the 

 internodes near the base are 10 inches long. The leaves are all green and perfectly sound, with the 

 exception of those at the top, which have been crushed by the ventilator. The stem in no portion 



tWhether or not this is "Common Green" is a question. It may be "Striped Green." The latter is the more 

 likely hypothesis, as the rest of the row is of this variety. 



{Although a microscopic examination was not made it is probable that the cane was bacterially diseased. 



