Davis . — The Fertilization of Batrachospermum . 55 
various, and sometimes the body extends perhaps only a third 
the length of the trichogyne, sometimes almost to the very 
end. There are usually one or two rather prominent lobes. 
Such is the appearance of this body in the young trichogyne, 
and, the writer, in studying the development of the latter, 
came to the conclusion that it was truly a portion of the 
chromatophore of the carpogonium, and deserved to be 
mentioned as a definite structure in the trichogyne. We have 
said that the chromatophore in the trichogyne is very variable 
in its shape, and also in its position, for it lies now at the base 
of the trichogyne, again along the sides, and sometimes near 
the top. The boundaries of the chromatophore, which are at 
first distinct, become less definite as the trichogyne matures 
and, the outlines grow more irregular. The colour also 
changes. In the young trichogynes the tint is very similar to 
the colour of the chromatophore in the carpogonium, that is, 
a peculiar light green shade that sometimes has a bluish tinge 
to it. With age the colour fades, and often changes to 
a yellowish green tint. These outward changes in form and 
colour are accompanied by modifications in the structure of 
the protoplasmic body itself. The chromatophore is at first 
perfectly homogeneous in structure, but with the fading of the 
colour the body passes into a granular condition, consisting of 
many small portions of different sizes, each having more or 
less of the original green tint, and all imbedded in strands of 
granular protoplasm. This change in structure is illustrated 
in the upper portion of Fig. 2 , where the chromatophore is 
breaking up and becoming granular in texture. The process 
above described may be one of degeneration, and the writer 
has observed at different times very similar appearances in 
the cells of other Algae. However, it is doubtful if the 
structure ever entirely disappears from the trichogyne, 
although it may become so faint as to be noticed only by 
careful observations, with high powers of the microscope. It 
is true in general that the remains of this body are distinctly 
visible in most trichogynes, often with sufficient colour still 
left in them to make the writer feel confident of their nature 
