Ser. RHoposPERME®. Fam. Coccocarpea. 
Puate CXCIX. 
GIGARTINA MAMILLOSA, v4. 
Gan. Cuar. Frond cartilaginous, either filiform, compressed, or flat, irre- 
gularly divided, purplish-red; the axis, or central substance, com- 
posed of branching anastomosing longitudinal fibres; the periphery 
of dichotomous filaments, laxly set in pellucid jelly; their apices 
moniliform, strongly united together. ructification double, on dis- 
tinct plants; 1, external tubercles, contaiming, on a central placenta, 
dense clusters of spores, scattered among the filaments of the peri- 
phery. Gicartina (Lamour.),—from yyaprov, a grape stone; which 
the tubercles resemble. 
Gicartina mamillosa; frond flabelliform, dichotomous, plane, channelled; 
segments wedge-shaped, cleft; tubercles roundish or ovate, pedicel- 
late, scattered over the disc of the frond. 
GIGARTINA mamillosa, J. 4g. Alg. Medit. p.104. Endl. 3rd Suppl. p. 42. 
Mastocarpvus mamillosus, Kitz. Phyc. Gen. p. 398. 
CuHonpRrvs mamillosus, Grev. dig. Brit. p. 127. Hook. Br. Fi. vol. ii. p. 302. 
Wyatt, Alg. Danm. no.117. Harv. in Mack. Fl. Hib. part 3. p. 201. 
Harv. Man. p. 77. 
SpH#Rococcus mamillosus, 4y. Syn. p.29. Lyngb. Hyd. Dan. p. 14. t. 5. 
4g. Sp. Alg. vol. i. p. 260. 4g. Syst. p. 220. Hook. Fl. Scot. part 2. 
p- 102. Grev. Fl. Edin. p.295. Spreng. Syst. Veg. vol. iv. p. 336. 
Fucus mamillosus, Good. and Woodw. in Linn. Trans. vol. iii. p. 174. Turn. 
Syn. p. 237. Turn. Hist. t. 218. H, Bot. t. 1054. 
Fucus polymorphus, (fourth series) Lam. Diss. p. 3. t. 17. £. 37. t. 18. f. 38. 
Fucus echinatus, Stack. Ner. Brit. p. 65. t. 12. 
Fucus canaliculatus 8., Huds. Fl. Ang. p. 583. 
Fucus ceranoides, vars. Lightf. Fl. Scot. p. 916. Gmel. Hist. p.115. With. 
“arr. Vol. Iv. p. 99. 
Fucus alveolatus, Esper. Ic. p. 139. t. 70. 
Has. On rocks near low-water mark. Perennial. Winter. Common on 
all our rocky shores. 
Goer. Distr. Atlantic shores of Europe and North America. 
Descr. Root, amembranous expansion. Fronds tufted, from four to eight inches 
long or more, rising with an undivided stem or stipes, which is filiform at 
base, but almost immediately becomes compressed, and then flattened, 
widening gradually upwards till it attains from an eighth to a quarter of an 
inch in breadth. At an inch or two above the base, the stipe forks; and 
this mode of branching, repeated again and again, results in a many times 
dichotomous, flabelliform frond. The branches are more or less channelled 
by the introflexion of the margin; they are very commonly twisted, often 
in a spiral manner; and the upper ones are gradually more and more 
VOL. II. U 
