332 
THE SEAWEEDS 
of a proper involucre, forming many angular hyaline carpospores within 
the pericarp. Gonimoblasts double (rarely single) evolving successively 
from gonimolobes. Tetrasporangia sessile or pedicellate on the ramuli, 
singly or many on each articulus, oblong-spherical, triangularly divided, 
rarely transversely bipartite. Antheridia numerous, minute, similarly 
situated to the tetrasporangia. 
Callitli amnion multi fid urn Harvey. 
Fronds 2 cm. to 3 cm. high, erect, densely caespitose, alternately decom- 
positely branching, ecorticate to the base; branches and ramuli spreading 
to all sides, terminal corymbose, the corymbose upper and young branches 
erect and fastigiate, the lower and older branches rigid, patent, sub- 
divaricate, attenuate-obtuse. Tetrasporangia single in the axils, sparse, 
triangularly divided. Articuli of branches at base thick, length four times 
diameter; the ramuli cylindrical, length two-four times diameter. 
South Australia (Eastern Bays), Western Australia (Rottnest Island). 
C alii th amnion laricinum Harvey. 
Attachment a small disc. Fronds subsolitary, setaceous, or. ultra- 
setaceous, from 5 cm. to 20 cm. high, with an undivided leading stem closely 
set with lateral, alternate, virgate branches, which are either simple or 
pinnate ; the general frond is therefore either simply or doubly, sometimes 
triply, pinnate. Both the stem and all the larger and lesser branches are 
coated with cellules throughout, no articulation being externally visible 
except near the extremities and on the very young branches; the surface 
of the larger branches is smooth. All the young and smaller branches are 
closely set with minute, alternate, many times dichotomous, fastigiate, 
pellucidly articulate ramuli, which are 1 mm. to 2 mm. in length. Articula- 
tions of the ramuli five to three times as long as broad ; apices spreading 
obtuse. Favellae on the ramuli. generally consisting of two divergent lobes, 
ovate-oblong or acuminate. Tetrasporangia globose, lateral or axillary on 
the forks of the ramuli, sessile. Colour a deep brownish-purple, becoming 
darker in drying. Substance very soft in young plant; in older firm, not 
gelatinous. Adheres to paper. 
South Australia (Investigator Strait, Eastern Bays), West Australia, 
Tasmania. 
C allith amnion spine scens Kiitzing. 
Fronds slender, 6 cm. to 7 cm. high, primary and secondary branches 
distichous, everywhere clothed with minute verticillate ramelli; branches 
distant, patent, divaricate, subdichotomous, spinescent. Articulations of 
primary branches three to four times as long as broad, ramelli twice as 
long as broad. Tetrasporangia oblong, sessile at nodes of ultimate ramuli, 
hyaline, triangularly divided. x 
South Australia (Eastern Bays). 
