456 



On Ergot. 



Tulasne. The frequent occurrence of minute spliaerias on the 

 ergotted grains of grasses suggested to him that they were pro- 

 bably not accidental productions, as had been supposed, but were 

 organically connected with the ergot, and represented a further 

 stage of its development. With the view of testing this opinion, 

 he planted a number of ergotted grains, and had the satisfaction 

 to find that a considerable proportion produced sphacrias. Those 

 produced by the ergot of rye were the same in form and structure, 

 with what were grown from the ergots of most of the other 

 grasses, and believing them all to belong to the same species, he 

 gave to it the name of Claviceps purpurea (Fig. 17). This perfect 



Fig. 17. 



a. Ergot of Wheat proaucing the pmall Fungus, CJaviceps purpurea, Tul. b. One of the heads 

 magnified, c. Section through a head, to show the aivities containing the spores. (From 

 Tulasne.) ^ 



plant is a small purplish fungus, with a spherical head, sup- 

 ported on a short firm stem, with a somewhat downy base. The 

 globose head is rough with small prominences, which are the 

 openings of the cavities or conceptacles in which the spores are 

 produced (Fig. 17, b and c). One of these conceptacles, highly 

 magnified, is shown in Fig. 18, a, representing the oval cavity 

 filled with the long slender spore cases (asci) springing from 

 the base of the cavity. The mouth of the conceptacle opening 



