104 



DISEASES OF CROPS. 



damage to the rye crops of Germany and Holland. The 

 disease known by the names of " knopf," " riib," and 

 "stock," is due to injury caused to rye plants by the 

 above-named nematoids. 



The Wire-worms, already described, seriously in- 

 jure rye plants. 



'<1 



Fig. 40. — The Ergot op Eye, etc. (ClavicepspurjguTea)* 



A. An ear of rye with ergots (a). 



B. A Bectdon through an ergot (in its early condition)'; at b is a myceliom 



bearing conidia ( x 270). 



C. A germinating ergot (a sclerotimn), (nat. size). 



The Ergot of Rye (Cftaviceps purpurea, Figs. 40 

 and 41) is nothing more than a sclerotimn or compact 

 hard mycelium of the above-named fungus. The ergots 



