356, 
Symbiosis in the Roots of the Ophioglossacez.* 
By Gero, F. ATKINSON. 
* While studying the structure of the root of Botrychium Vir- 
gimanum, yellowish protoplasmic masses in certain cells of the 
cortical parenchyma, producing a strong contrast with the starch 
content of the other cells of the cortex, attracted my attention. 
Close examination and treatment with reagents showed the exist- 
ence in the cortical parenchyma of the root of a symbiotic fungus 
stimulating the cells to the development of a rich protoplasmic 
content. . 
The organism is located at quite a definite portion of the cor- 
tical parenchyma, about one-third to one-half the distance from 
the epidermis to the central cylinder. In transections of the root 
it appears in the form of a ring entirely encircling the root, or 
only occupying an arc of a circle. From this localized center 
numerous threads extend to the epidermis and the outside of the 
root. 
Since the roots of the Ophioglossacez do not possess root-hairs, 
or only a slight development of them, it occurred to me that pos- 
sibly the presence of this symbiotic organism was universal in the 
roots of the order. Accordingly, several species, both of Botry- 
chium and Ophioglossum, most of them in the Horace Mann her- 
barium of Cornell University, were examined. In all of them the 
presence of the fungus was determined. 
The species examined, together with the localities, are here 
appended : ; 
Botrychium matricariefolium, B. ternatum and B. Virginianum, from 
New York. 
B. lanceolatum, Massachusetts and Vermont. 
Bb. subbifoliatum, Hawaiian Islands. 
B. Lunaria, Clova Mountains. 
Botrychium (No. 484, Drummond's Collection, Boston Soc. Nat. 
Hist.) Louisiana. 
Ophioglossum vulgatum, New York and suburbs of Paris. 
i 
* Read before the Section of Botany, A. A. A. S., Madison Meeting, August, 1893- : 
