218 
THE SEAWEEDS 
Martensia elegans Hering. 
Inconspicuously forked, flabellate. Margin not toothed. Colour when 
growing brown-fawn, on drying red. 
South Africa, Australia from Fremantle to Newcastle. 
I regard the large fragments thrown up at times and labelled M. 
australis and M. gigas by Harvey as being coarse “old man” forms of M. 
elegans. 
NITOPHYLLUM Greville. 
Fronds flat, expanded in one plane, or narrow, almost linear dichoto- 
mous or pinnate, more usually broader cuneate-flabelliform or palmatisect, 
sessile or stipitate. Fronds thinly or more firmly membranaceous, consist- 
ing of one or more strata of rounded or angular sub-hexagonal cells filled 
with colouring matter usually rose-coloured but sometimes of a duller red 
or purple, the surface cells giving to the frond, as seen from the surface by 
aid of the microscope, a beautifully areolated appearance. Cystocarps^and 
tetrasporangia borne on different individuals. Cystocarps sessile on the 
frond, depressed, with a wide basal placenta which bears clavate-ovate car- 
pospores within a radiate cellular pericarp through an opening in which 
(carpostomium) the spores escape. Nothing seems to be known of the 
antheridia. The tetrasporangia are rounded, divided tetrahedrally into 
four spores, and occur in definite groups (sori) which may be scattered 
over the surface or be local in their disposition. 
A world-spread genus, with about 24 Australian species. It has been 
divided up into small new genera by Kylin. 
KEY TO THE SUBGENERA. 
J. Agardh divided the genus into four subgenera, basing his classifica- 
tion on the development of the veins. 
1. Leptostroma. — Monostromatic, veinless,. European. 
2. Aglaophyllum. — Di-pleio-stromatic, veinless. 
3. Cryptoneura . — Di-pleio-stromatic, veins present inconspicuous. 
4. Polyneura. — Di-pleio-stromatic, veins well developed, conspicuous. 
Subgenus Aglaophyllum. 
Three species have been recorded from South Australia, N. Gunnianum. 
N. erosum , and N. prist oideum. 
A. — Frond shortly stipitate, thinly membranaceous, 
veinless, the margins densely undulate, pro- 
duced into oblong laciniae. Cystocarps chiefly 
on the laciniae. Colour rose-red N, crispum 
(Kuetz) J. Ag. 
B. — Frond dilated with broadly cuneate segments, 
the margin armed with small teeth bent 
alternately upwards and downwards, visible 
under a lens N. Gunnianum 
Harvey. 
XMyriogramme Gunniana (Harv.) Kylin). 
