Germination of Teleutospores of Ustilaginee 89 
secondary spores as effectually, as when two or three have 
become connected, the only difference being that with 
fused or conjugated spores larger germ-tubes and larger 
secondary spores are produced. The secondary spores 
(Plate VI. Figs. 9, 10) are at first cylindrical, but they soon 
become reniform, and at length, by the attenuation of their 
ends, more or less crescent-shaped. They may be pro- 
duced from any part of the primary spores, even from the 
connecting bridge, and at almost any distance; very 
seldom is more than one produced from each fused pair of 
primary spores. Three or more primary spores have been 
seen connected,* and double fusion between two has been 
also observed.f Not only do the primary produce second- 
ary spores, but they may emit a pointed germ-tube, for 
direct penetration of the host-plant. In like manner, 
between the secondary spores all sorts of connections and 
conjugations or fusions occur, with the same emptying of 
the contents from. one spore into the other (Figs. 11, 12). 
The secondary spores are, however, essentially the spores 
the germ-tubes of which enter the host-plant. 
In nahrldsung, according to Brefeld, the primary and 
ae are larger, and are produced in greater 
abundance. No conjugations or fusions occur, except 
when it becomes exhausted. The primary spores, how- 
ever, comport themselves very differently in néhrlosung ; 
they send out germ-tubes which are narrower than those 
given off by them: in water. These tubes are unseptate, 
but branch and inosculate with each other so as to form 
a mycelium (Plate VI. Fig. 14), which, as it grows out 
into the air; forms a white floccose mass. For five or 
six days no secondary spores are found in well-nourished 
mycelia, whereas spore-formation occurs soon in badly 
‘nourished ones. The spores are produced only on those 
* Brefeld, /oc. cit., t. xiii. fig. 39. t Ibid., fig. 38. 
