112 THE AUSTRALIAN NATURALIST. 
The female plants produce a structure which is composed 
of two parts; a more or less spherical lower portion which con- 
tains the egg cell and an elongated portion known as the tricho- 
gyne. The portion containing the egg cell is known at this 
stage as the carpogonium. ‘Two lateral auxiliary cells are also 
formed. When the egg cell is ready for fertilisation the tricho- 
gyne exudes an apparently attractive mucilage which attracts 
the spermatia. One of these spermatia enters the trichogyne, the 
envelope which the spermatium has by this time formed round 
itself and the wall of the trichogyne dissolving. The spermatium 
passes down the trichogyne and fuses with the egg cell. Fertili- 
sation is now complete. The fertilised carpogonium is cut off 
from the trichogyne by a partition, and the latter structure, 
having accomplished its mission, withers away. Short branches 
are sent out from the carpogonium, which appear to fuse with 
the auxiliary cells, though there is no fusion of the nuclei. Hach 
auxiliary cell divides by a transverse septum, and the upper part 
develops a number of carpospores. Thus two sets of fruits are’ 
formed from each female fructification. These structures to- 
gether are known as the cysto-carp and the individual spores 
formed are called the carpospores. This method of reproduction 
is typical of Callithamnion. On germination each carpospore 
gives rise to a plant which bears asexual tetraspores, and thus, it 
is seen, there is a very definite and regular alternation of gene- 
rations, in the species. 
THE “LIZARD ROCK,” MOSMAN. 
By Tos. STEEL. © 
In the “Mosman Daily” there appeared the following para- 
graph by “Observer” descriptive of this curious rock at the 
Cremorne wharf in Mosman Bay :— 
“Australians are proud of the natural beauties of ‘their 
country, of the mountains and caves with their curious sculp- 
ture, but I wonder how many of the thousands of passengers 
’ travelling to and fro on the Mosman ferries have observed the 
huge lizard which nature has fashioned on the top of a rock 
just at the Cremorne landing. He appears to have crept partly 
forth from his retreat under a smaller rock, showing his head, 
shoulder and fore arm. His expression varies, though the 
mouth always wears a cruel look; eye and nostrils are well de- 
fined. Sometimes, especially on grey dull days, he seems to 
be on the alert for prey, watchful and sinister; but in bright 
