38 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Old nodules, large Where a small number of the plants (less 

 £ inch- J inch, and than 25 per cent.) had large nodules, 

 brown £ inch-£ inch diameter . . . XXX 



Where 25 percent, of the plants had large, 



old nodules, £ inch-£ inch diameter XXXX 



The distinction between early and late attacks by the worms as 

 they ascended from the subsoil is fortunately well illustrated in the 

 results of the first season, 19 15. In that year the tomatos were 

 hurried off in order to grow a crop of cucumbers for the autumn. 

 The roots of the tomatos were examined as described and a record 

 taken. When the cucumber roots were taken up in November it was 

 found that sometimes the cucumbers were nodulated on the places 

 where the tomatos had not been attacked. Of course, wherever 

 the tomatos had been attacked, the cucumbers were, later on, more 

 heavily infected. This result is indicated in Table III., 



where p (present) means Nodules found. 



a (absent) means No Nodules found. 



Tomatos were grown in the soil from March to August 1915, and 

 cucumbers grew in the soil from August to November 1915. 



Results of Season 1915. 



In judging the results of the first season (1915) it is helpful to place 

 side by side : 



1. The result of the tomatos and cucumbers in respect of the 

 mere absence or presence of nodules. (Table III.) 



2. The degrees of infection of each plot at the beginning and end 

 of the season. (Table IV.) 



3. The list of substances which in one way or another were harmful 

 to the tomatos. (Table V.) 



Tables III., IV., V. — Analysis of Results of Season 1915. 



III. IV. v. 



No. 

 of 

 Plot. 



Nodules in 

 Tomato 

 Roots. 

 p= found 

 a = not found. 



Nodules in 

 Cucumber 



Roots. 

 p=found 

 a«=not found. 



Degree of 

 Infection at 

 End of 1914 

 Season. 



Degree of 

 Infection at 

 End of 1015 



Season. 



Injurious 

 Effect on 

 Tomatos. 



I 



a 



a 



X 



O 





4 



a 



a 



XXXX 



O 





5 



a 



a 



XXXX 



O 



i 



6 



a 



a 



XX 







7 



a 



a 



XXX 



O 



i 



8 



a 



a 



X 



O 





9 



a 



a 



X 



O 





1 1 



a 



a 



x 



O 



i 



21 



a 



a 



XX 



O 



i 



22 



a 



a 



XX 



O 



i 



23 



a 



a 



XXXX 



O 



i 



24 



a 



a 



XXX 



O 





26 



a 



a 



XX 



O 





