FUNGOUS ROOT-TUBERCLES. 73 



This is quite different from the conditions in the alder (38) 

 and Neottia Nidus avis (22), where the fungus is finally ab- 

 sorbed by the so-called digestive cell and the nucleus resumes 

 its natural processes. However, it seems that the normal ad- 

 joining cells may utilize, in some manner, the remaining 



The turgidity of the 

 host cell becomes less and less and the surrounding cells 

 crowd it into a smaller space, so that none of the earlier struc- 

 tures of the fungus or of the host can be recognized. No 

 nucleus ever reappears, and thus the history of host cell and 



Though Shibata has de- 



oUS 



fun 



scribed, in Alnus, certain protoplasmic structures, called 

 "Secretkorperchen," which in some way dissolve the fungus 

 so that it may be utilized as food by the host cell, and Zach 

 (58) has noted similar conditions in Elaeagnus as well as in 

 the alder tubercles, nothing of such a nature occurs in 

 Ceanothus. 



THE ROOT TUBERCLES OF ELAEAGNUS. 



Warming (52) was the first to give a full account of the 

 tubercles occurring on the various genera of the Elaeagnus 

 family, although he credits Jorgensen with being the first to 

 note the tubercles on the roots of Elaeagnus, Hippophde and 



Shepherdia. Accompanied 



mo 



Their cause, he 



mvxomvcete resembling Plasm 



phora brassicae. 



men 



claims that thev resemble spores or are identical 



with them. 



Later Brunchorst (6) made an intensive study of the 

 tubercles of Elaeagnus angustifolia and Hippophde rham- 

 noides in connection with those of Alnus glutinosa. He con- 



ngus to be the same in both plants and 



true 



Elaeagnus. 



More recently Zach (58) has also made a com 

 of the tubercles on Elaeagnus angustifolia and t 

 sa in which he points out that the hyphom 

 nlants belongs to the same genus and species: 



both 



