6o6 
Williams . — 77z<? Gametophytes and 
In many cases the eggs are observed to have partly disintegrated after 
emergence. It is not known at present whether this is due to bursting, or 
to absence of fertilization. While most of the new plants remain attached 
to the empty oogonium, many become detached and float away. Under 
natural conditions this probably occurs far more frequently. 
The new sporophyte grows rapidly ; it is positively heliotropic, so that 
its direction of growth is quite different from that of the gametophyte, and 
it is far more regular in its sequence of divisions and in its resulting form. 
If a preparation be stained with a very dilute solution of polychrome 
methylene-blue the gametophytes are left uncoloured, but the young 
sporophytes become at once very prominent owing to the deep pink or 
purple colour of their cell-walls. The deeper colour occurs in the younger 
parts ; here the minute structure of the wall is very interesting. Further 
description must be deferred to a future paper. 
The first rhizoid makes its appearance early in the form of a rapidly 
growing, very long protrusion from the basal cell of the sporophyte. This 
often applies itself in its early stage to the outer surface of the empty 
oogonium, but, so far, the writer has never observed a case where it entered 
the oogonium. 
The corresponding stages in Chorda , through agreeing with the above 
in their main features, present interesting differences of detail. The 
gametophytes are many times bigger than those of Laminaria. They 
branch again and again in a very irregular manner until they appear like 
so many miniature bushes. While there is a distinct difference of size 
between the two kinds of gametophyte, it is never so extreme as in 
Laminaria. Owing to the long time taken to mature, there is a greater 
uncertainty and consequent difficulty in securing the critical stages than 
in the former, and, as it is impossible to obtain pure cultures, the long delay 
enables other organisms to grow and multiply. A still greater difference 
is seen in the mode of emergence of the egg. The oogonial wall swells 
but a very little; the outer layer bursts, and the contents, instead of 
completely emerging, grow out still enclosed in the extensible inner wall 
of the oogonium. The emergent part is thus still in communication with 
the oogonial cavity, and, though the bulk of the contents have migrated 
out of the latter, a few chloroplasts and granules remain in it. Reinke’s 
well-known figure of a Chorda germling shows this well, but he failed to 
observe the torn edges of the aperture, which forms a more or less distinct 
collar or sheath indicating the position of the former apex of the oogonium. 
It follows from what has been said above that the anchorage of the new 
sporophyte to the gametophyte is more secure here than in Laminaria . 
That the enclosing membrane is not very firm is proved by the occurrence 
of rare cases where the plantlets break off at the collar. For the same 
