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BOTANICAL CONTRIBUTIONS. 
The Roots and Mycorhizas of some of the Monotropaceae. 
By D. T. MacDovuGat and Francis E. Lioyp. 
(With Plates ro, 11 and 12.) 
The members of the family Monotropaceae are chlorophyl- 
less without exception and have the roots sheathed with a 
heavy mycelial layer of an ectotropic fungus. The symbiosis 
between the fungus and the higher plant is complete, and this 
family exhibits the most marked adaptations to the mycorhizal 
habit of any of the seed-plants, and in them we may observe 
the extreme development of a physiological tendency which 
has recently been found to be so widespread. The adapta- 
tion in question appears to be of very ancient origin in this 
family and has been followed by very sweeping degenera- 
tions of the roots and shoots. Both members have been re- 
duced to such an extent that it would not be possible for any 
species of this family to endure an extended period in the ab- 
sence of the fungal symbiont. 
It is of interest to note that in AZonotropa is found the first 
known example of a mycorhiza, or adhesion of a fungus to 
the roots of a higher plant. This discovery dates back to 
1832 when E. Fries wrote of the ‘fungus roots” of Jfono- 
tropa, which were clothed with a Zudurcinia (2). Since 
that time a score of investigators have touched upon various 
features of the morphology and physiology of Monotropa 
unifiora and Al. Hypoprlys. So far as the examination of 
the mycorhiza has been made attention has been paid chiefly 
to AZ. Hypopitys which is now placed in a separate genus. 
The development and mycorhizal adaptations of Sarcodes 
were described by Oliver in 1890 (6). Sarcodes, Schwesn- 
vtsta, Monotropa, Hypopitys, and Plerospora were treated 
as parasites by Chatin (1) in disregard of the accumulated 
evidence bearing upon the true nature of the group. Singu- 
larly enough this author does not hesitate to discuss the 
