THE CROWN gall: CULTURAL CHARACTERS 453 



Fig. 344. — A. Slow-growing crown-gall embryoma on mango. In the center 

 (under X) a folded (twisted) green bud. Notice also a bud at the extreme left, 

 one in the right upper corner, one below it, and one in the center under the main 

 growth. These five I have counted as one of the six centei's of embryonic growth. 

 See Fig. 343. This embryonic portion was under observation many weeks but 

 it developed no shoots. X 4.5. 



B. Cross-section of a very young orange fruit showing crown-gall tumors in 

 the placental region. Bacterium iumefaciens (hop through sunflower) was in- 

 oculated February 1, 1916, by needle pricks into the very young ovary. Two 

 locules are infected, the others are normal. No shoots developed. Orange VI, 

 fixed March 10, 1916. Slide 1198A6, stained with acid fuchsin and methyl green. 

 The tumor tissue stains red. Actual diameter of the section (short way) l^ inch. 

 Photographed with 75 mm. planar. 



