Ser. MELANOSPERMEiE. Fain. Ectocarpea. 



Plate CLXII. 



ECTOCARPUS SILICULOSUS,* Lyngb. 



Gen. Char. Frond capillary, jointed, olive or brown, flaccid, single-tubed. 

 Fruit either spherical, elliptical, or lanceolate utricles (or spores), 

 borne on the ramuli, or imbedded in their substance. Ectocarpus 

 (Lt/ngb.), — from cktos, external, and Kaprros, fruit. 



Ectocarpus siliculosus ; tufts yellowish or pale olive green, gelatinous, 

 soft ; filaments very slender, excessively branched ; ultimate branchlets 

 alternate or secund, attenuated ; utricles stalked, subulate, attenuated 

 to a fine point. 



Ectocarpus siliculosus, Lyngb. Hyd. Ban. p. 131. t. 43. Ag. Syst. p. 161. 

 Grev. Fl. Edin. p. 314. Ag. Sp. Alg. vol. ii. p. 37. Harv. in Hook. Br. 

 Fl. vol. ii. p. 325. Harv. in Mack. Fl. Hid. part 3. p. 181. Harv. 

 Man. p. 40. Wyatt, Alg. Damn. no. 172. /. Ag. Alg. Medit. p. 26. 

 Endl. 3rd Suppl. 21. Kiitz. Phyc. Gen. p. 288. 



Ceramium siliculosum, Ag. Syn. p. 65. Hook. Fl. Scot, part 2. p. 86. 



Ceramium confervoides, Roth, Cat. vol. i. p. 151. t. 8. f. 3. and vol. hi. p. 148. 



Conferva siliculosa, Bilhc. Syn. no. 112. t. E. Sm. Eng. Bot. t. 2319. . 



/3. longipes ; stalks of the utricles very long. 



Hab. Parasitical on various marine Algae, between tide marks, and in 

 three to four fathom water. Annual. Spring to Autumn. Very 

 common. /3. at Jersey, Miss White. 



Geogr. Distr. Atlantic shores of Europe and North America. Mediterranean 

 Sea. 



Descr. Filaments from three to eighteen inches long, densely tufted and exces- 

 sively branched, very slender, the main branches more or less entangled 

 together, in old specimens especially, into slender rope-like bundles, the 

 lesser branches free, spreading on all sides, long, and set with feathery 

 branchlets furnished with lateral byssoid ramuli. Branches and ramuli 

 alternate, or subsecund, issuing at acute angles ; the latter long, and 

 tapering to a point. Joints from once and a half to twice as long as broad, 

 pellucid. Utricles broadly subulate, or somewhat lanceolate, closely trans- 

 versely striate, tapering to a fine point, and occasionally produced at the 

 apex into a hyaline filament. In our var. /3. (fig. 4 K 5.) the utricles are 

 borne on very long stalks, but not otherwise different. Substance very soft, 

 somewhat gelatinous, soon decomposing, closely adhering to paper in 

 drying; sometimes more harsh and coarser. Colour varying from olive 

 green to yellowish or brown. 



This is one of the commonest species of Ectocarpus in the 



* Erroneously printed reticulonu, in the list given at the end of our first 

 volume. 



