Formation of Teleutospores of Ustilaginee. 63 
entering the ovary through the flower-stalk, sends its 
hyphz through the funiculus into the ovule, which becomes 
permeated by densely interwoven hyphe. The micro- 
; pylar end of the integuments alone escapes and remains, as 
a cap on the top of the diseased ovule, for some time, 
Fig. 4.—Sphacelotheca hydropiperis (Schum.) A, Ovary and perianth of Polygonum 
hydropiper affected with S. hydropiperis. B, The same more advanced, showing the micro- 
pylar cap (c). C, Section of ovary and perianth at an early stage 5 & the style; o, the 
integument of the micropylar end of the ovule; / wall of the ovary; Z, the perianth. The 
spore-formation is seen to be commencing above, and the rudimentary columella is visible. 
D, Section of a more advanced ovary, showing the walls of the receptacle and the columella 
(c). Slightly magnified. (De Bary.) 
but eventually falls off. The hyphe develop partly into 
spores and partly into the receptacle. The latter consists 
of a thick external case with a central columella. The 
cells of which it is composed are but loosely compacted, 
colourless, and about the size of the spores, The least 
injury fractures this case and allows the escape of the 
