WILT OF CUCURBITS. 



273 



but 4 days later there was no wilt. On July 14 the pricked leaf was shriveled but the rest of the vine 

 was normal. 



(303.) Cucurbita digitata. Wilt began on the fifth or sixth day in the middle of the pricked part. 

 The seventh day in the central part of the pricked area the tissue for 0.7 sq. cm. was dead and yellow- 

 white. Outside of this was a narrow border of freshly wilting tissue, but five-sixths of the leaf was 

 still normal. Two days later the whole of the pricked blade and the upper two-thirds of the petiole 

 had shriveled. The eleventh day the second leaf was beginning to yellow and droop. On July 14 

 the pricked leaf and the first leaf up had shriveled. The rest of the vine was normal. 



(304.) Trichosanilies cucumeroides (from Agr. college in Japan). The seventh day the tip of the 

 pricked leaf was wilting but 2 days later most of the pricked leaf was normal and the wilt seemed 

 to be dying out. The eleventh day a fresh part of the leaf had begun to wilt. On July 14 the 

 whole of the pricked leaf had shriveled. The rest of the vine was normal. 



(305.) Trichosanilies cucumeroides. The pricked leaf showed no signs up to June 25. The 

 eleventh day about one-third of the apical (pricked) portion of the inoculated leaf-blade had wilted 

 but was not yet dry. On July 14 the pricked leaf had shriveled, but the rest of the vine was normal 

 and was growing rapidly. 



(306.) Trichosanilies cucumeroides. There was no result from the inoculation other than local 

 injury which did not appear until after June 27 (eleventh day). On July 14 the pricked leaf had 

 dry-shriveled but the remainder of 

 the vine was normal and growing 

 rapidly. 



(307.) Passiflora incarnala. 

 The seventh day a whitish callous 

 had formed around each of the 

 pricks and there was no wilt. Up 

 to July 14 there had been no result 

 even in the pricked leaf. 



(308.) Passiflora incarnala. 

 Like the preceding. No result. 

 There was no wilt or change of 

 color even in the pricked leaf. 



(309.) Cue tint is niclo var. 

 dud aim (ripe fruit yellow and like 

 a small round gourd; delightful 

 odor; taste like muskmelon). The 

 inoculation was made in an old 

 leaf. The seventh day there was a 

 distinct wilt in and around the 

 pricked area. This had begun in a 

 small way the preceding day. Two 

 days later about one-fourth of the 

 pricked leaf-blade was wilted. The 

 blade of this leaf measured 3.5 X3.5 

 inches. On the eleventh day the 

 whole of the pricked leaf-blade 

 was dry-shriveled. On July 14 the 

 whole plant was dry-shriveled. 



(310.) Citrullus vulgaris. The 

 seventh day there was no wilt and 



it looked as if a cork-layer had formed around the pricks, at least there was a narrow yellow rim 

 around each prick (estimated 0.1 mm. wide). The plant was examined June 25, 27, July 3 and 14. 

 There was no result even in the pricked leaf. This leaf had received 67 pricks. 



(311.) Echinocystis lobata. Wilt appeared the sixth day in the pricked portion of the inoculated 

 leaf. The seventh day nearly the whole of the pricked leaf had wilted and 2 days later the whole 

 pricked blade including the tip of the petiole had shriveled. This leaf was separated from the one 

 above by an internode of 4 inches and that leaf was still normal. The first leaf below was 4 inches 

 down and that too was unaffected by the wilt. The eleventh day the plant had developed as fine 

 a case of the bacterial wilt as could be desired. The pricked leaf had entirely shriveled, including 



Fig. 78. Cross-section of petiole of Cucurbita foetidissima, showing a bundle occupied by Bacillus tracheiphilus 

 as result of a pure culture inoculation on lamina of leaf. For orientation see fig. 77, which was made, however, 

 Drawn from slide 254 B x, with the Abbe camera. Plant No. 273 



from another section. 



