THE GAMETOPHYTES OF EQUISETUM LAEVIGATUM" 
EtpaA R. WALKER 
(WITH PLATES XXIII, XXIV AND THREE FIGURES) 
Introduction 
According to BucHTIEN (1), gametophytes of Equisetum were 
‘first found by VAuCHER in 1826, and later by Biscuorr in 1829, 
and MitpE in 1852. The finding of Equisetum gametophytes, 
however, has beenrare. When in August 1916, Ropert A. NESBIT, 
at that time a student in the University of Nebraska, found large 
numbers of them near Tekamah, Nebraska, it was hardly expected 
that the discovery would soon be repeated. The gametophytes, 
however, have since been found in several localities, usually in Ne- 
braska, by a number of persons. At the suggestion of Dr. CHARLES 
. CHAMBERLAIN the writer undertook a study of these gametophytes 
with the results here reported. 
Distribution 
The discovery of Equisetum gametophytes by Mr. NESBIT 
called the attention of local botanists to the possibility of finding 
them. The result is that they have been observed in recent years 
as follows: 
Robert A. Nesbit, Tekamah, Nebraska, August and September 1916; 
N. F. Petersen, Osborn, Indiana, August 2, 1917; Manhattan, Kansas, Septem- 
ber 1917; Reno, Nevada, July 1918; Pilger, Nebraska, September 25, 19203 
Lincoln, Nebraska, October 9, 1920; Florence, Nebraska, November 5, 1920; 
South Sioux City, Nebraska, November 7, 1920; F. C. Jean, Peru, Nebraska, 
August 1917; Elda R. Walker, Doris Hayes, and Katherine Wolfe, Lincoln, 
Nebraska, October 12, 17, 24, and November 14, 1920. 
, Since learning of these recent observations, Professor O. A. 
STEVENS has told the writer of finding a considerable number of 
Equisetum gametophytes on the banks of the Big Blue River and a 
drainage ditch emptying into it, at Manhattan, Kansas, in Septem- 
Contributions from department of botany, University of Nebraska, new series, 
no. 33. 
Botanical Gazette, vol. 71] [378 
