4o8 
Notes. 
of which form transverse plugs in the lumen of the hair, and come 
to look like walls. Later still, the highly refracting bodies 1 appear 
in the protoplasm, and in the adult hair it is they that look like 
transverse partitions. 
Similarly, I have examined the hairs on a specimen of Aphanochaete 
repens , Br. 2 , contained in the British Museum. Here the masses were 
very distinct inside the hairs, and did not at all have the appearance 
of transverse walls. Specimens from various localities in the Royal 
Botanic Gardens at Kew have also induced me to accept Huber’s 
explanation, and led me to the assumption that septate hairs do not 
occur at all in either Aphanochaete or Herposteiron. 
In a young Stigeoclonium the hairs develop in exactly the same way 
as in Aphanochaete. The zoospores on coming to rest have an 
elongated, elliptical shape, bearing a great resemblance to some 
species of Characium. At the one end a hair very soon begins to 
form, this end becoming colourless, and gradually growing out to 
form the hair. This rapidly lengthens, and becomes segmented, so as 
to form a long multicellular structure. Soon after this is well 
developed, the young plant becomes two-celled by the formation of 
a transverse wall. No branching takes place until it is several cells 
in length (cf. Fig. 22, 3); — -generally 2-3 lower ones filled with 
chlorophyll, succeeded by one or two with sparing contents, these 
leading off to the absolutely colourless cells of the hair-tip. The 
lowest cell then first puts out a lateral process, which rapidly increases 
in size, and soon the second cell shows signs of branching, this 
branch being developed either on the same or on the opposite 
side (Fig. 22, 4). 
After what has been said above, there is thus no longer any reason 
for believing that multicellular hairs occur at all in either Herposteiron , 
Nag., or Aphanochaete , Berth. Further, it seems very probable that 
Hansgirg’s observations 3 on the occurrence of a sheath in Aphano- 
1 The development of the hair would seem to indicate that these are derived 
from the protoplasmic plugs referred to in the text ; and the yellow colour taken 
on with chlor-zinc-iodide shows them to be proteid in their nature. I tried the 
Xanthoprotein-reaction on them with little success ; there was a trace of colour- 
ation, but generally the acid was too much for the delicate hairs. These bodies 
are insoluble in alcohol and xylol, so that they do not consist of any fatty sub- 
stance. They remain dark in polarised light. 
2 Phycotheca Boreali- Americana, No. 762. — Collins, Holden and Setchell. 
3 Flora, 1888, p. 214. 
