Observations on the "Slime-fiuxes" of trees. i8i 



been injured in some way and are probably to be attributed 

 to an accumulation and subsequent outflow of phloem materials. 

 Yeasts and bacteria %rith gelatinous sheaths develop very rapidly 

 in these exudations. Inoculation experiments of the organisms 

 on healthy bark were unsuccessful, so that here again we must 

 conclude that the flux is of physiological origin. Nothing 

 abnormal was found in the constitution of the tissues from which 

 the fluxes originated [cf. Holtz(9H p. 126). 



The practically constant occurrence of the fungoid and yeast 

 forms described in the case of both bro\^Ti and white fluxes is 

 rather remarkable, and must be attributed to the nature and 

 reaction of the food supply. 



The difference between the constituents of the fluxes found 

 by the writer and those described from the Continent are rather 

 marked. This coincides somewhat with the obser\'ations of 

 Hansen and tends to support the \'iew that the fungi and yeasts 

 are of no importance as causative agents. 



If the \^Titer's theory concerning the origin of the shme-fluxes 

 is correct, it would suggest the futiht}- of painting or tarring 

 wounds of trees from which fluxes are already flowing. Apple- 

 trees have been noticed on which fluxes on the branches have 

 broken through a thick coating of tar. 



As suggested by pre\ious workers, the flux material may prove 

 deleterious to the tree b}' inducing the growth of spores of such 

 fungi as Poly par us squamosns and CoUyhia velutipes. The \\Titer 

 has often seen the fructifications of CoUybia associated with 

 fluxes on elm. 



In conclusion I wish to express my warmest thanks to Mr 

 F. T. Brooks at the Botany School, Cambridge, under whose 

 supervision these investigations were carried out, for much 

 personal help, and encouragement on all occasions. 



SUiDIARY. 



1. Investigations have been carried out on certain peculiar 

 exudations from the trunks and branches of elms, horse-chest- 

 nuts, apples, willows, etc. 



2. The reddish flux of Huntingdon elms was found to be 

 composed of a Fusarium forming copious pink spore-masses, 

 an Oospora [Oidiiim), bacteria, and other casual organisms. 



3. The brown flux of elms and horse-chestnuts invariably 

 contained a species of Oospora. An Oospora [Oidium), a sporing 

 yeast and a Fusarium were commonl}' found, but not constantly. 

 It also contained fluorescent bacteria, algae, insect larvae, etc. 



4. The flux of apple trees, found in and near Cambridge, 

 always contained three kinds of non-sporing yeasts. 



5. The white flux of willows contained an Oospora [Oidium) 



