Lamprothamnus alopecttroides, A . Braun . 67 
Transitions from rhizoid to pro-embryo. There are sometimes tran- 
sitions from a rhizoid formation to a pro-embryo (Nordstedt, J 66). A long, 
thread-like rhizoid, divided in the characteristic way by oblique walls, may 
cut off cells at its apex to form the ‘ Vorkeimspitze/ leaf-node and rhizoid- 
node (Fig. 6) as already described. In such a case the extent of the pro- 
embryo cannot be defined, unless we consider it to be simply the internode 
below the rhizoid-node proper, in which the rhizoids are formed by the 
cutting off of peripheral cells, and all the cells above this rhizoid-node. 
Nevertheless, as there are so many cases in which an extra oblique node 
occurs below the rhizoid-node, when the extent of the pro-embryo is 
obvious, such a distinction is rather arbitrary. 
With the further growth of the young plant of Lamprothamnus , as in 
the case of other Characeae, a branchy having a dome-shaped apical cell 
capable of continued division and the formation of whorls of leaves, is 
generally formed at the rhizoid-node proper (Fig. 1 b). This branch first 
grows out at right angles to the pro-embryo, but soon turns upwards to the 
surface of the mud. Occasionally an accessory pro-embryo arises from the 
rhizoid-node (Fig. 5). 
Pro-embryo arising from the oospore . The few oospores which had 
germinated did so in late autumn. The pro-embryos formed, seemed weak 
and liable to the attacks of a fungus : they were all in a young stage, and 
the 6 Vorkeimspitze * cells had not swollen. I found two cases in which 
an interposed oblique node was formed between the spore and the rhizoid- 
node (Fig. 7). The primary root, formed from the spore, divides by an 
oblique wall in the manner characteristic of the rhizoids of the group, and 
from the node so formed four rhizoids arise. Later, other rhizoids are 
formed from this node, and extra rhizoids arise from the ‘ Samenknoten ’ (Pr.) 
or primary rhizoid-node (Nordstedt) situated at the apex of the spore. 
A bnormal Plants. (1) Springing from a root-node on which were two 
tubercles, I found a young pro-embryonic plant, which, instead of showing 
the usual rhizoids springing from the rhizoid-node, showed about nine 
rounded tubercles of various sizes, evidently formed directly from the node- 
cells. Not a single cell had grown out in the ordinary way to form 
a rhizoid. Between the rhizoid-node and the node from which the pro- 
embryo sprang, rows of small starch grains were deposited. The grains in 
the different tubercles were of different sizes, varying directly with the size 
of the tubercle itself. 
(2) Another abnormal case occurred in which at a rhizoid-node 
showing the S-shaped oblique wall, there arose, together with one or two 
rhizoids, a rounded tubercle filled with starch grains. The tubercle had 
formed chlorophyll and was of a bright green colour. Arising from the 
same node and in close proximity to the tubercle was a single leaf 
segment made up of about five cells. It would seem that this part of 
