THE FUNGI WHICH CAUSE PLANT DISEASE 211 



turns to orange-color and the perithecia appear, forming a 

 layer. 



Echinodothis Atkinson (p. 199) ''* 



Stromata subfleshy or corky, light-colored, pulvinate to sub- 

 globose or irregular in form, often constricted at the base, some- 

 times entirely surrounding the host, consisting of several layers of 

 different consistency; perithecia superficial, scattered, subcylindric, 

 sessile, giving an echinulate appearance to the stroma; asci cylin- 

 dric, 8-spored; spores linear, septate, at length separating at the 

 septa into short segments. 



Two species, parasitic on grasses in the warmer parts of the 

 western hemisphere. 



E. tuberiformis (Berk. & Rav.) Atk.''« 



Stromata subglobose, 1 cm. or more in diameter, entire, lobed, 

 or divided, seated upon the reed or upon the leaf-sheath and .fas- 

 tened by a whitish mycelium consisting of radiating threads which 

 are sometimes tinged yellowish-brown; substance leathery or corky, 

 consisting of three layers, an inner layer white to pinkish, an inter- 

 mediate layer light ochraceous and an outer layer cinnamon; 

 stroma externally dark brownish becoming black; conidiophores 

 needle-shaped; conidia ovoid to fusoid, 3-4 x 7-10 n; perithecia 

 entirely superficial in small clusters or evenly distributed over 

 the exposed surface of the stroma, subconic in form, giving the 

 whole stroma a spiny appearance, clothed except the apex with a 

 dense covering of minute threads which are at first whitish, be- 

 coming cinnamon colored, the naked apex becoming black, about 

 0.3 X 1 mm.; asci cylindric, with a swelling at the apex, very large, 

 475-750 X 14-20 m; spores nearly as long as the ascus, hyaline or 

 slightly yellowish, many-septate, the joints 15 x 4-5 fi. 



On Arundinaria in the Southern States. 



Asciculosporium take Miy."' forms witches' brooms on bamboo 

 in Japan. It is closely related to Dusiella and Epichloe. 



Claviceps Tulasne (p. 199) 



Sclerotium formed within the hypertrophied tissues of the 

 ovary of the host, succeeding the conidial stage which is a 

 Sphacelia; stroma erect, with a long sterile base and a fertile, 



