80 



use Its reserve material for the annual ring. In the fall the trees 

 were examined, and the above results as to increase in growth 

 were obtained, also the fact, that while nearly every vestige of 

 starch had been used up by the cambium layer, the amount of 

 nitrogenous matter in the woody tissues was not less than that of 

 normally growing trees. 



Prof. Hartig suggests the following explanation of these facts : 

 In normally acting trees, the cambium possesses only a slight 

 power of dissolving and attracting to itself the reserve material 

 within the tree, its need of nourishing matter being satisfied by 

 the supply brought to it by the inner sieve tubes of the rind. 

 When this supply is no longer furnished, as in case of the trees 

 deprived of tlieir smaller branches, the hungry caml)ium possesses 



a strong power of attraction, by which it is enabled to draw out 



the entire store of reserve materiaL Now, as it is quite evident 

 the extra amount of reserve material is not designed for pathologi- 

 cal purposes, it suggested itself to him that it was for the purpose 

 of producing a large supply of seeds, and that the periodical re- 

 currence of seed and not seed years was due to the respective 

 amounts of reserve stores in the tree. A number of interesting 

 experiments are given by which this assumption was fully cor- 

 roborated. Our space does not allow the citation of these, but 

 the reader is referred to the article itself, in the Botanisches Cen- 

 tralblatt, Vol. ^6, No. 13, 1888. It must be mentioned, how- 

 ever, that in conclusion, Prof. Hartig admits the desirability of 



similar tests being applied to other trees before making the state- 



ment too general, yet he says it is not probable that the red beech 

 would prove an exception as to its use of reserve material. 



E. L. G. 



Hytnenoconidium petasaUmi is the name of a new and remark- 

 able fungus, discovered by Hugo Zukal of Vienna, and described 

 by him in a late number of the Botanische Zeitung.* Some olive 

 branches with half-grown fruit had been sent him from Fiume, 

 with the question as to the cause of the diseased condition of the 

 tree from which the branches were taken. On the fruit appeared 

 separate spots of a wrinkled, discolored appearance, and between 



January 25, 1889. 



