58 Davis . — The Fertilization of Batrachosperrmim. 
latter. The antherozoids usually attach themselves near the 
tip of the trichogyne, and commonly at the very end. There 
seems to be no rule as regards the position of the nucleus 
in the antherozoid at the time of fertilization. It very 
frequently lies at the side farthest away from the point of 
fusion, as in Figs. 6 and 7, or it may be found very near the 
point of contact. The writer, after examining many specimens 
in the condition shown in Figs. 6 and 7, has never seen any- 
thing to indicate that the nucleus of the antherozoid or any 
portion of it moves rapidly into the trichogyne. The position 
of the nucleus of the trichogyne, as has been stated, is some- 
what variable ; that of the carpogonium usually lies near the 
base of that structure, but sometimes occupies a position 
above the middle portion. As it is not difficult to determine 
these points in this species, the writer does not see how any 
marked change in the nuclear conditions of the structures 
could have escaped his examination. There do not seem 
to be any violent changes in the position of the nuclei effected 
by the act of fusion. Gradual changes will be spoken of 
later. Frequently more than one antherozoid may be attached 
to the trichogyne, but the evidence indicates that only one 
fuses. The writer has examined this point with considerable 
care, and has never seen more than one antherozoid of a group 
in undoubted union with the protoplasm of the trichogyne. 
It is very interesting to note the manner in which all the 
antherozoids of a group around a trichogyne extend towards 
that structure so that their shape is changed from a round 
outline to an oval. They not only extend towards the tricho- 
gyne, but sometimes towards each other. 
We will now consider the manner in which the trichogyne 
is separated from the carpogonium. The experiments tried 
upon living plants, as well as the writer’s observations, seem 
to prove that the trichogyne never becomes separated from 
the carpogonium unless fertilized. The strand of protoplasm 
connecting the two structures is originally rather wide (see 
Fig. 6) ; and the first indication that the trichogyne is to 
become cut off from the carpogonium is shown by the 
