150 



FUNGI. 



days a little obtuse tube is protruded through the epispore, 

 bearing at its apex long fusiform bodies, which are the sporules 

 of the first generation. These conjugate by means of short 

 transverse tubes, after the manner of the threads of Zygnema. 



Afterwards long elliptical 

 sporules of the second gene- 

 ration are produced on short 

 pedicels by the conjugated 

 fusiform bodies of the first 

 generation. (Fig. 89, ss.) 

 Ultimately these sporules of 

 the second generation germi- 

 nate, and generate, on short 

 spicules, similar sporules of a 

 third generation. (Fig. 89, 



St.} 



In Ustilago (flosculorum) 

 germination takes place 

 readily in warm weather. The 

 germ tube is rather smaller 

 at its base than further on. In 

 from fifteen to eighteen hours the contents become coarsely 

 granular ; at the same time little projections appear on the 

 tube which are narrowed at the base, into which some of the 

 protoplasm passes. These ultimately mature into sporules. 

 At the same time a terminal sporule generally appears on the 

 threads. Secondary sporules frequently grow from the primary, 

 which are rather smaller, and these occasionally give rise to a 

 third generation. 



In Urocystis (pompJiolygodes) the germinating tubes spring 

 exclusively from the darker central cells of the clusters. From 

 these are developed at their extremity three or four linear 

 bodies, as in Tilletia, but after this no further development has 

 as yet been traced. It may be remarked here that Waldheim 

 observed similar conjugation of the sporules in some species of 



FIG. 89. Germinating pseudospore (g) of 

 Tilletia caries with, secondary spores in con- 

 jugation. (Tul.) 



ii. (1847), p. 113; Tulasne, second memoir, in "Ann. des. Sci. Nat." ii. (4< 

 ser.), p. 77 ; Cooke, in " Journ. Quekett Micro. Club," i. p. 170. 



