100 DISEASES OF FIELD & GARDEN CROPS. [CH. 



the same scale in the other illustrations given in this 

 work. 



The three larger spherical brown bodies seen in Fig. 

 37, and the single example in Fig. 38, are resting-spores 

 of the putrefactive fungus of cabbages and turnips, named 

 Peronospora parasitica, Pers., and sometimes seen in great 



K-200 



FIG. 37. CLUB-ROOT DISEASE OF TURNIPS. 



Spores of Plasmodiophora Brassicce, Wor., seen within the Cells of Turnip- 

 root. Enlarged 200 diameters. 



abundance in turnip plants reduced to putridity by the 

 combined attacks of the Peronospora and the Plasmodio- 

 phora. These larger bodies are the second species of 

 Artotrogus (not A. hydnosporus] of Montagne. 



The Plasmodiophora spores remain uninjured and in a 



