On Ergot. 



457 



through the conical swelling is obvious ; this gives the granular 

 aspect to the head of the fungus. Four of the sacs or asci are 

 represented at b, still more magnified. They are seen to be 



Fig. 18. 



a. ilagnified section of a Conceptacle, showing tbe slender spore-cases, and the tumid mouth of 

 the cavity, b. Spore-cases magnified, c. Single spores. (From Tulasue.) 



filled with slender needle-shaped bodies, which are the ultimate 

 and perfect reproductive spores of the ergot. A few of these 

 spores are represented still more magnified at c. 



Having traced the history of the ergot, we may now inquire 

 how and at Avhat time the crops get infected, with the view of 

 seeing whether it is possible to discover any means of alleviating, 

 if not of destroying, this injurious parasite. 



At two different stages in the life of ergot, bodies are produced 

 which have the power of propagating the disease, namely, the 

 spores of the perfect fungus developed from the ergot, or the 

 " spores " (spermatia or conidia) of the early sphacelia state of 

 the parasite. 



The plant is carried over the winter in the dormant ergot con- 

 dition. A large proportion of the ergot in a field, when it is 

 fully ripe, falls to the ground during the operations of the harvest, 

 or by the friction of the spikes against each other through the 

 action of the wind. These ero:ots remain on the <rround during- 

 the winter without undergoing any change. They are dormant, 



