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that a very moist atmosphère existed between them ; most 

 of thèse cases occur where some leaves on the top of a 

 branch already killed by the fangus, are hanging on the 

 rhizomorphous strands. (Fig. 2). For one can always see, 

 that a myceliumstrand, which looks almost like a rhizo- 

 morph, passes from the branch to the leaf. This strand 

 can be followed rather far over the leaf surface; first 

 following the midrib, then crossing the leaf blade. (Fig. 1 

 and 2). 



The strand, before passing from the branch to the 

 leafstalk, first spreads over the thicker parts, which are 

 formed round each node; it forms a very thin membrane, 

 from which in the majority of cases several strands ori- 

 ginate; one of them runs to each leaf, one to each ofthe 

 axillary shoots, (when thèse are already developed) and 

 one or more to the top of the branch. The development 

 of the fungus is always acropetal; nor did I succeed in 

 causing a basipetal growth by artificial inoculations. One 

 may follow the strands along the branches in succeeding 

 order down to the mainstem, but I never succeeded in 

 finding the fungus less then one or one and a half feet 

 from the ground, notwithstanding I investigated a good 

 number of trees. Nor did I notice any sign of hyphae on 

 the roots of plants, which were heavily attacked. 



The colour of the strands varies from light to darkbrown ; 

 on the younger branches the strands may be lifted up as 

 well as the délicate membrane on the leaves. Because this 

 membrane is so very délicate, the best manner to take it 

 from the leafsurface is by holding one ofthe rhizomorphous 

 strands with tweezers. 



When the leaf is still green, one may see the cobweb 

 as a silvery-white tissue; very soon the colour grows 

 darker, so that when the parts, which hâve been attacked 

 are dried up and dark brown, the hyphae show a somewhat 



