302 



USTILAGINEAE. 



mycelium Form.s a stroma on the ovary-wall ; there the 



spores originate and pass out to the peripliery as they attain 

 maturity. The spores adhere in Ijlack 

 ^ masses, and germinate in water in the 



following spring. A promycelium is pro- 

 duced, and on emerging into the air 

 becomes divided by means of a cross- 

 septum towards its apex ; from both 

 cells so formed conidia are developed 

 and grow out into germ-tubes without 

 previous sprouting. This species occurs 

 on many species of Cartx, and the 

 mycelium perennates in the rhizomes. 

 The spores vary somewhat on the 

 different hosts. 



C. subinclusa (Korn.) (U.S. America). 

 The spores form coal-black masses in the 

 ovaries of many species of Carcx.. They 

 develop on a stroma from within out- 

 wards, and are more easily detached than 

 those of C. caricis; their coat-markings 

 also take the form of thicker and shorter 

 processes. On germination in water 

 after a resting period, the spores produce 

 two-celled promycelia, from the apical 

 cell of which an ovoid conidium is 



abjointed, while from the lower cell a lateral conidiophore is 



produced. Xumerous conidia are given off from both cells, and 



grow out without previous sprouting. 



C. (1) sorghi {Endothlaspis sorghi) Sor. The inyceliuni envelopes the grain of 



Sorghum cernuum, and fills it with black sijore -masses. It has only been 



observed in Asia, 



Other species of Cintractia occur outside of Europe, but are of in) 



practical importance. 



Fic. l&i. — Cintractia caricis. 

 Two ovaries have been replaced 

 by black spherical fungus-fruits ; 

 an isolated normal triangular 

 ovary is shown in longitudinal 

 and cross section, (v. Tubeuf 

 del.) 



Sphacelotheca. 



The sporocarp is sharply detiiied, and consists of a columella 

 round which the loose mass of spores is disposed, the whole being 

 enclosed in a covering formed by non-sporogenous hyphae. 



Sphacelotheca hydropiperis (Schum.). De Bary describes 



