220 BOTANICAL GAZETTE [SEPTEMBER 
NOTES FOR STUDENTS. 
BEFOKE THE Botanical Society of America, at the Columbus meeting 
Professor D. T. MacDougal read a paper on Symbiosis and saprophytism, oh 
which the following is a synopsis : 
At the last meeting of the society I read a paper in description of my work 
upon a large number of herbaceous mycorhizal plants,? and a short note was 
presented before the meeting of the Society for Plant Physiology and Mor 
phology, in December 1898, in which a delimitation of the terms saprophyte 
and symbiosis was attempted. Attention was also called to the fact that 
only two seed plants, Wullschlgelia and Cephalanthera, may be truly des 
ignated as saprophytes, all other species of so-called holosaprophytes being 
symbiotic with mycorhizal fungi. a 
. During the last year my efforts have been directed first to ascertain the 
adaptations undergone by these true saprophytes, and compare such changes 
with those undergone by mycorhizal forms. Secondly, evidence which might 
have a bearing upon the physiological relations of a seed plant and its 
mycorhizal fungus has been carefully sought for. 
Cephalanthera, the saprophyte examined, showed alterations in structure 
generally similar to those of mycorhizal forms; but, in exception to the major 
ity of chlorophylless species, it retains the stomata of the leaves, and has 
developed no underground transpiratory organs. ky 
The roots, unlike those of most mycorhizal forms, are deeply buried in the 
soil, on account of which the number of good herbarium specimens to be 
found is extremely small. Two types of these organs are present : a fibeenyy 
with a reduction and fusion of the stelar components, and with radially elo® 
gated cortex. This variation has hitherto been regarded as a result dm 
presence of a fungus as in mycorhiza, while as a matter of fact It's goed 
tation to humus foods. The second type of root is devoted to storage an silk ; 
a normal multiplication of the cortical elements. Both types per 
with the two kinds of roots formed by Wullschlegelia, which still 
e chemical 
ferentially 
have taken place, entailing also unusual osmotic conditions. 
two seed saprephytes live like fungi, although capable 0 
The coralloid formations on the offsets of Calypso, which are 
Norway to Washington, have been examined, and the result of ne eh 
ment of these adventitious mycorhizas is quite similar a coupled 
described in Aplectrum. The occurrence of the coralloid mycorhiz@ BY” © 
-® Published in the Annals of Botany 13:—. March 1899- 
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