Ser. MELAN0SPERMEJ5. ( 151 ) Fam. ECTOCARPE^:. 



SPHACELAKIA SERTULARIA.— 5o;mm. 



Gen. Char. — Fronds filiform, articulated, dichotomously branched ; apices of the branches 

 generally more or less distended, as if the apical cell was enlarged and inflated, 

 containing in its centre a dark granular mass of endochrome. Fructification : 

 "elliptical utricles (or spores), furnished with a limbus, borne on the ramuli." 

 Name from (rcpuKeXos, " a gangrene, " in allusion to the withered, diseased-like 

 apices of the branches, very characteristic in some of the species. 



Sphacelaria sertularia. — " Frond slightly shaggy at the base, weak 

 and slender, irregularly branched ; branches somewhat lanceolate or 

 linear, horizontally patent, tripinnate, pinnae alternate, divaricate, 

 pinnules very patent, multifid ; axils all very obtuse and wide." — Phyc. 

 Brit. 



Sphacelaria sertularia. — Bonnem. sec. Lenorm. in Herh. ; Harv. P. B. plate 143 ; 

 Harv. Man. p. 55 ; Harv. Syn. p. 49 ; Atlas, plate 18, fig. 76 ; 

 /. G. Agardh, Sp. Gen. Alg, vol. i. p. 35. 



Sphacelaria ^Zicma, fi patens. — Harv. Man. 1st edit. p. 37. 



Hab. — Parasitical on various Algse, in three to twenty fathoms water. Eare. Perennial. 

 Brighton {Mr. Borrer) ; Torbay {Mrs. Griffiths) ; Isle of Wight {Miss KirJcpatrick) ; 

 Jersey {Miss White, Mr. F. P. Girdlestone) ; Carrickfergus {Mr. M'Calla) ; Eoundstone 

 Bay {Dr. Harvey). 



Geoqr. Dist. — Atlantic shores of France ; south of England and Ireland. 



Description. — Fronds very slender, about an inch or an inch and a 

 half in length, much tufted and matted together, interwoven with other 

 filiform Algse, in-eg-ularly pinnate ; pinnae of very irregular length, some- 

 times bare of such below, at other times pinnate to the base ; at one time 

 the middle pinnae are longest, at another those at the ends, or several series 

 of long and short pinnae alternate ; pinnae again pinnate or bipinnate, 

 each series shorter, all very patent or even recui-ved, ultimate pinnules 

 somewhat erect, the apices obtuse. Pinnae and pinnulae mostly alternate, 

 but frequently irregular or defective, sometimes all are secund ; the two 

 lower pinnvJes on each pinna often on the same side, the others gene- 

 rally arising from each joint alternately ; the pinnae from each alternate 

 joint. Articulations about as long as broad, longitudinally striated, 

 siphons four; "the ultimate ramuli monosiphonous." Substance rather 

 rigid, not adhering to paper. Colour, a rather pale olive green. The 

 apices of the pinnulea are more frequently sphacelate than those of the 

 last species. The fructification we have not seen. 



