304 |. DR. LILY BATTEN ON 
Habitat. Occurring near low-water mark and at greater depth on rocks, 
corallines, and shells. Flourishes where conditions are turbulent. Common. 
British Records. Orkney Islands, Forres, Peterhead, Arbroath, Elie, Earls- 
ferry, Dunbar, Berwick, Alnmouth, Whitley, Folkestone, Brighton, Isle of 
Wight, Swanage, Weymouth, Sidmouth, Torbay, Plymouth, Torpoint, 
Falmouth, Penzance, Jsle of Man, Portincross, Arran, Cumbrae, Bute, South 
and West coasts of Ireland, and the Channel Islands. 
Distribution in Europe. Atlantic shores of Europe as far south as France. 
2. P. FÆTIDISSIMA Cocks, Alg. Fasc. Coll. Brit. Seaweeds, 1855, no. xxix 
[nomen |. 
P. stuposa Zanard. ex Kützing, Tab. Phye. xiv. 1864, p. 18 (diagnosis) : 
Ralfs in Penzance Nat. Hist. Soc. Trans. 1884, p. 325 [nomen]. 
References. De Toni (22) iv. p. 924; Hauck (31) p. 240 e seq.; 
Bornet (10) p. 154 [314]. 
Icones. Kützing, Tab. Phyc. xiv. 1864, p. 18, tab. 49 (d-4). — Ewsiccata. 
Cocks, Alg. Fasc. Coll. Brit. Seaweeds, 1855, no. xxix. 
DESCRIPTION.— Habit. Occurring in tufts from 3-10 ems. in length. 
Branching alternate or pseudo-dichotomous, branches being clothed with 
numerous ramuli, especially in the upper parts. Substance gelatinous. 
Stphons. 8-10 pericentral sometimes bounded by a row of corticating 
cells at the base. Colour. Brownish-red. Anatomy. Articulations from 
1-2 or seldom three times longer than their breadth in the upright parts 
of the plant, and about equal to their breadth in the prostrate portions 
near the attachment organ. Attachment organ. Numerous rhizoids formed 
from the pericentral siphons or the corticating cells when the latter are 
present, the rhizoids developing disc-like expansions at the tips when they 
encounter a firm substratum. Reproductive organs. Tetraspores intercalary 
in development, borne in swollen ramuli. Cystocarps ovate in form, with a 
conical elongation towards the ostiole. 
According to Hauck (31. p. 240), the species is ecorticate, but in the lower 
parts of the main branches a row of corticating cells sometimes occurs, the 
individual cells of which alternate with the pericentral siphons. The ramuli 
are described by De Toni (22. p.924) as having “apice non penicilliferis,” but 
in a specimen obtained from Swanage, April 1919, there were clusters of 
filamentous hairs at the tips of the ramuli. The error is probably due to the 
previous examination of the plant having taken place at a different time of 
the year. When the plant grows on another alga, e. g. Codium adherens 
(Durlston Head, Swanage), attachment discs are not developed at the tips of 
the rhizoids; a holdfast is obtained by the latter ramifying among the cells 
of the host. 
Habitat. On rocks, stones, and on other alge such as Codium adhwrens 
between the tide-levels. Very rare. 
British Records, Brighton, Swanage (Batten, 1919), Plymouth, Falmouth, 
and Newlyn West. 
Distribution in Europe. Adriatic Sea. 
