114 



ASCOMYCETES. 



piila; on Onions. U. viola forms large dark-violet swellings in the leaf-stalk 

 and stems of Violets. Thecaphora (Fig. 102) appears in seedlings of Con- 

 volvulus and Astragalus. 



As a means of protection against the Smut-Fungi which make their appear- 

 ance on the different cereals, a submersion of the grains in a solution of blue 

 vitriol (J%) for twelve hours, or better still, submerging for five minutes in 

 water heated to 53-55 C (Jensen's method) is employed. 





FIG. 102. Thecapliora. 1, T. convolvuli, a ball of spore?, one of the brand-spores has emitted 

 a septate branched conidiophore ( x 520). 2, T. nffniis, a ball of spores (x 520). 



Class 3. Mycomycetes, Higher Fungi. 



The MYCOMYCETES are not entirely aquatic in habit ; they have 

 hyphae with transverse watts, but no sexual reproductive organs. 

 The asexual reproduction takes place in very different ways ; by 

 endospores (in asci), conidia, basidiospores, chlamydospores, and 

 oidia. Swarmspores are never found. 



Two chief methods of reproduction may be distinguished, and 

 hence the class may be divided into two large sub-classes : the 

 ASCOMYCETES (with asci), and the BASIDIOMYCETES (with basidia). 



Sub-Class 1. Ascomycetes. 



The main characteristic which distinguishes the Ascomycetes is 

 the ascus ; a name given to a sporangium of a definite shape and 

 size, and containing a definite number of spores. The shape is 



