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THE SEAWEEDS 
or four principal branches. Main branches bi-tripinnate, ovate in circum- 
scription; pinnae closely set, ereeto-patent, alternate; pinnules similar, 
gradually shorter towards the apices; the margin in every part of the 
frond, except the denuded bases of old stems, furnished with minute, 
forked, trifid or four to six-fid ramuli, about 2 mm. long, subulate, trans- 
versely striate; colour dark reddish-brown when dry. Cystocarps ovate- 
globose, wide-mouthed, sessile, on the sides of the marginal teeth. Stichidia 
distorted or forked, formed from the marginal teeth, which are then very 
much developed and multifid. This species varies very much in width. 
South Australia (Encounter Bay, LeFevre Peninsula, Investigator Strait, 
Eastern Bays), Western Australia, Victoria, Tasmania. 
Bictymenia angusta J. Agardh. 
Frond 18 cm. to 25 cm. high, areolate, with narrow linear pinnae ; pin- 
nellae conspicuous, irregular, alternate. The pinnae in the young plant are 
somewhat fan -shaped, in the fully developed plant are more or less uneven ; 
the ends of the pinnellae are strongly penicillate, and subcorymbose ; the 
adult pinnellae alternately pinnatifid. Substance membranaceous. 
South Australia (Eastern Bays, Encounter Bay). 
Bictymenia spinulosa Kiitzing. 
Frond slender, branched at the base, rami long, longitudinally ribbed, 
winged, margin irregularly toothed; at the apex tri-pinnatifid, and 
pyramidal. The pinnellae narrow and spinose, fertile. Cystocarps globose, 
sessile. Substance rigid. 
South Coast of Australia. 
Bictymenia TIarveyana Sonder. 
Frond 12 cm. to 30 cm. long, to 2 mm. broad, gelatinous-membranous; 
areolae obsolete ; alternate or irregularly pinnate, the margin in every part 
furnished with minute, forked, trifid or four to five-fid ramuli, about 2 mm. 
Fig. 129. — Dictymenia Harveyana : a, plant; b, part of a frond, enlarged. 
