EXPERIMENTS WITH THE DAISY ORGANISM. 41 



sand. They have, therefore, been under conditions such as would 

 not produce a rapid growth. The inocuhited tissues were rather 

 woody, and this probably explains the small number of infections 

 (50 per cent). 



DAISY ON RASPBERRY. 



Inoculations of April 12, 1907 (Smith). 



Thirty- two raspberry plants, 16 of the Cuthbert variety and 16 of 

 the King variety, were inoculated with agar streak cultures 6 days 

 old, 15 to 20 punctures being made on each plant. Eight plants of 

 each variety were held as checks. The inoculations were made in 

 the laboratory and the plants immediately afterwards set out in pots 

 in the greenhouse. 



Result. — June 27, 1907: These plants were from a nursery in Vir- 

 ginia. They were small and not very satisfactory to work with, and 

 they grew badly when potted, partly because they were of inferior 

 stock and partly because of insufficient water at times. For these 

 reasons a good many of them died on the start. The conditions, 

 therefore, were unfavorable to the success of the inoculations. 



Thirteen plants of the King variety and 6 of the Cuthbert pro- 

 duced no tumors. Ten plants were mfected (2 King, 8 Cuthbert) 

 with 32 tumors, many at the point of inoculation. Three plants were 

 missing. 



The tumors on all these plants are white and growing, except one 

 or two which are decaying or dead. The largest at point of inocu- 

 lation were 10 by 10 by 10 mm., 15 by 15 by 10 mm., 18 by 14 by 

 14 mm., and 20 by 15 mm. 



July 2, 1907: The checks were brought in and examined. They 

 had been in another hothouse adjoining the one where the inoculated 

 plants were kept. They proved to be badly infected, so that no 

 conclusions could be drawn from the experiment. There was no 

 possible danger of infection from the cultures used, because they 

 were not opened, nor any moculations made, until after the check 

 plants were punctured with a sterile needle and set out in the other 

 house. The checks have gro^vn more than the inoculated plants and 

 the infection was probably brought along with them from the nursery, 

 because one or two knots were found on the roots of these plants 

 when they were purchased. 



The details on checks are as follows: Eight Kings, 4 diseased with 

 5 tumors; 7 Cuthberts, 5 diseased — on No. 298 whole root occupied, 

 about a dozen tumors as big as peas and others like filberts in clusters. 

 On the others, 13 tumors. One of the two plants free from galls 

 was dead. 



213 



