492 Harper—Nuclear Phenomena in the Smuts. 
the fused spores which the author suspects might be the 
nuclei. In two cases one of these refractive bodies was seen 
in the fusion tube but prolonged observation revealed no 
change in its position. Popta says nothing of changes 
in the spore pairs which follow fusion. De Bary ! , how¬ 
ever, has recorded that after fusion the pairs enlarge very 
considerably as is the case in the anther smut. According to 
De Bary also when the fused pairs germinate but a single 
tube is pushed out and the entire protoplasmic content of the 
pair passes out into the young mycelium thus formed. The 
germination regularly occurs on the surface of a host plant 
and the germ tube at once penetrates the tissues of the host 
plant and continues its vegetative existence there. 
The nuclear phenomena during these germination stages 
should be investigated before we can be entirely certain that 
a sexual fusion of nuclei does not occur at any stage of the 
process; though the phenomena are very similar to those in 
Sclerotinia, where the number of spores which combine is so 
large and variable as to practically exclude the assumption of 
sexuality. 
Further in this connection should be mentioned Hoffman’s 1 2 
clamp connections between adjacent cells of the mycelia of the 
Basidiomycetes. The more exact investigation of these struct¬ 
ures is to be credited to Prof. Brefeld. 3 He finds that in the 
mycelium of Coprinus a tube grows out from the end of one cell 
and curves in toward the lateral wall of the next adjacent cell, 
with which it comes in contact and finally fuses, forming thus- 
an open passage between the two cells. Later a transverse wall 
is built at the base of the fusion tube, so that the continuous 
passage way formed between the two cells is again interrupted. 
Brefeld thinks the structure has something to do with circulation 
of food materials in the mycelium. Its resemblance to the fus¬ 
ion of the cells of the promycelia in the smuts has already bee n 
pointed ou t. 
1 Beitr. zur Morph. u. Phys. der Pilze, I. 
2 Hoffman, Bot. Zeitung, 1856; p. 156. Also De Bary, Morph., Phys., u. 
Biol, der'Pilze, Bakt., und Mycetozoa, pp. 2-3. 
8 Brefeld, Vinters. iXber Schimmelpilze, III, p. 17. 
