OF SOUTH AUSTRALIA. 
215 
(3) Laciniae serrate P. Mertensii 
(Grev.) Harvey. 
South Australia (Encounter Bay, 
Eastern Bays). 
4. Sporophylls clustered in a dense glomerulus, 
single with simple branches, pedicellate. 
Laciniae entire, subulate. Rami broad, sub- 
ecostate, 3 mm P. patagiatum 
J. Agardh. 
Tasmania. 
5. Sporophylls simple, clavate oblong, pedicellate, 
clustered in the axils. Laciniae serrate. 
Rami broad, thickened medially or with a 
less developed midrib, 3 mm 
South Australia (Eastern Bays). 
Family DELESSERIACEAH (Naegeli) Schmitz. 
Fronds mostly flat, sometimes latticed, simple or variously lobed, costate 
or ecostate, parenchymatous. Procarps disposed in the mid-stratum of the 
thallus. Gonimoblast sessile in the thallus evolved in a cavity covered by 
a cortex adnate to the middle of a thickened placenta. Carpospores at the 
apices of fertile ramuli. Tetrasporangia often collected in sori. or borne 
on special leaflets, triangularly divided. “In this family are included per- 
haps the most beautiful of all algae. Rose-red in colour, leaf-like, some with 
midribs (and veins), some with a delicate or net-like structure, all are 
remarkable for their attractive form.” (Tilden.) 
P. dilatatum 
J. Agardh. 
