:
P l a t e LXXXIX.
PYCNOPHYCUS TUBERCULATUS, K ütz.
Gen . C h a e . Root composed of branching fibres. Frond cylindrical, dichotomous.
Air-vessels, -when present, innate, simple. Receptacles terminal,
cellular, pierced by numerous pores, which communicate with
immersed, spherical conceptacles, containing, in the lower part of the
receptacles, parietal, simple spores, and in the upper, tufted antheridia.
P y cn o p h y cu s (Kiitz.),—from m m s , thick, and rjivKos, a i
P ycnophycus tuherenlatns.
P ycn o ph y cu s tuberculatus, K itz . Phyc. Gen. p. 359 (1843).
Cym adu se tuberculata, Bne. Ann. Sc. Nat., 1845. p. 12.
Fucu s tuberculatus, Huds. M. A,ig. p. 588. Good, and Woodw. in Linn.
Trans, vol. iii. 198. Turn. Syn. Puc. vol. ii. p. 505. Turn. Hist. t. 7.
Plsper, Ic. Puc. Yol.ŸL.-ÿ.23. i . \ 2 \ . P. Bot. t. 126. Lamour. Pss. p. 23.
Stack. Ner. Brit, append. Ag. Sp. Alg. vol. i. p. 98. Ag. Syst. p. 279.
Spreng. Syst. Veg. vol. iv. p. 316. Grev. Alg. Brit. p. 18. Hook. Br. PL
vol. ii. p. 269. Harv. in Mack. PI. Hib. part 3. p. 169. Harv. Man. p. 21.
Wyatt, Alg. Banm. no. 103. Pndl. 3rd Suppl. p. 29.
Fuous bifurcatus. With. vol. iv. p. 109. 1 .17. f. 1.
H a b . In rock-pools left, on the recess of the tide, near low-water mark ;
never growing in places which are dry at low-water. Perennial.
Summer and autumn. Several places on the coast of Cornwall, Hudson,
Stackhouse, Turner, &o. Ilfracombe, Bishop Goodenough. Bül
of Portland, ifî-. Aryer. North of Ireland, Br. Scott (sec Tu rn ).
Abundant on the west coast of Ireland, in several places, from Galway
to Cork. Jersey, Miss White and Miss Turner.
Geoge. D is t e . Atlantic shores of France and Spain. Coast of Barbary, Web.
and Mohr. Cape of Good Hope, Bowie and W. H. H.
D e s c e . Eoot, formed of branching fibres, which extend in patches from one to
several feet in diameter, over tbe surface of the rock. Pronds 12-20 inches
long, as thick as a goose-quill, cylindrical, erect, quite simple for the distance
of from four to eight inches from the root, then forked ; and afterwards
repeatedly, but irregularly, dichotomous, one of tbe arms of the fork
being longer and stronger than tbe other, so tbat eventually the frond
often appears as if alternately branched. Axils obtuse, rounded. Vesicles
frequently absent ; when present, generally innate in the ultimate branches,
or immediately below one of the upper forkings. Eeceptacles terminating
the branches, from a prolongation of which they are formed, simple, cylindrical,
obtuse, composed internally of compact cellular tissue; the cells
polygonal. They are, when ripe, tuberculated, each tubercle pierced by a
pore, beneath which is placed a spherical conceptacle. In the lower part of
the receptacle, the conceptacles contain numerous parietal, simple, elliptical
spores, narrowed at their lower end ; in the upper part, they are destitute
of spores, but filled with tufts of branching filaments, to which antheridia
are attached. Colour, when growing, a clear olive, more yellow, and semiiafh
ill