364 BOTANICAL GAZETTE {MAY 
but remain at the mouth, uncoiling and coiling again and lashing 
about with their posterior ends. Since other sperms enter at the 
same time, it is difficult to explain these movements as being due to 
an injurious effect of the substance extruded from the archegonium. 
On several occasions a peculiar reaction of the sperms was 
observed. This resembled the darting movements often seen in a 
swarm of gnats and will be described as the “darting reaction.” 
Sperms exhibiting these movements collected in a fairly definite 
region, and showed almost constant motion, keeping one end still 
and swinging the other end about, or darting about in the field, here 
and there, with constant changes in their direction of movement. They 
move in every direction, sometimes approaching the archegonium, 
sometimes passing it, sometimes going away from it. Occasionally 
one proceeds in a fairly direct spiral to the boundary of the region, 
then turns directly back, approaches the archegonium, and resumes 
its darting movements. Such sperms usually do not enter the arche- 
gonium directly, but may wander in and out of the mouth. Some, 
however, remain in the archegonium, so that an accumulation of 
sperms finally occurs within the archegonial neck. A few of the 
sperms leave this field, but most of them remain in it until they die. 
Other sperms upon entering the field show the darting reactions 
immediately, and usually react by turning back whenever they 
approach the boundary of the region. This collection usually occurred 
in front of an open archegonium, but sometimes at other places, 
presumably where some of the cells of the prothallus were injured. 
The movements described were shown especially in the reactions of 
sperms of the same species and of other species toward the arche- 
gonia of Athyrium Filix-joemina, but were not shown in every case 
of entrance in this species, and were shown in a few cases of entrance 
in other species. 
It now remains for us to consider which of the views stated above 
will best explain the movements and reactions described. We w 
first sum up the observed facts. It has been shown that any inter- 
ference with the movements of sperms, whether by jelly, thick ink, 
a salt solution, or attachment to a solid particle, produces a series of 
complex movements; the sperms swing their anterior ends through 
large circles, at the same time rotating on their axes, and then go 
