44 THE LARCH CANKER 
septate, and in this case the germ tube is developed rather 
earlier than when the spore becomes segmented, and it 
may appear as soon as twenty hours after the ejection of 
the spore. This method of germination is less common 
than the last, but very many cases were observed, and 
the spores did not afterwards become septate. Hither 
one germ tube grows out terminally, or one from each end; 
in one case two germ tubes appeared at the same end 
(fig. 20, c). 
The germ tubes vary in size (the larger ones are about 
4 broad), and may grow to a considerable length without 
branching. One unbranched hypha attained a length of 
140 » in less than twenty-six hours. But generally the germ 
tubes branch when they are much shorter than this and 
form a fairly densely interwoven mass, even in tap-water 
without any added nutriment. The walls of these hyphae 
are thin and colourless. 
As the hyphae grow and use up the food at their dis- 
posal, they frequently fuse with each other. These fusions 
were observed by Willkomm, though his figures are mis- 
leading as to their method of formation. I have noticed 
three kinds of fusions. Firstly, when one hypha grows so 
as to meet another broadside, the apical wall of the one 
may be digested, and at the same time a hole be formed 
in the side of the other. In this case the former hypha does 
not continue its growth. Secondly, one hypha may grow 
over another and lie across it ; a clamp connexion may then 
be made, in the form of a branch, which grows out from one 
hypha and fuses with the other. I have not observed from 
which hypha this branch usually arises. It does not generally 
connect points which have been in contact, but is usually 
bent, and connects the side of the upper hypha with the 
top of the lower hypha. Thirdly, two hyphae growing 
parallel with each other 5-20» apart may each send out 
a branch hypha, and these two branches fuse by their 
apices. Possibly their meeting in this way is merely acci- 
dental, though the large number of fusions of this kind 
suggests that some stimulus attracts the two growing apices 
