Ser. MELANOSPERME/E. ( 195 ) Fam. ECTOCARPE.E. 



Plate CLXXXIL 

 ECTOCAEPUS MERTENSII.~^i/. 



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

 eitlier spherical, elliptical, or lanceolate utricles (or spores), borne (externally) 

 on tbe ramuli, or imbedded in their substance." Name from iicrhs, "external," 

 and Kapnoi, "fruit." A uame equally applicable to many other genera, and 

 unfortunately only to a few of the species in the present. 



EcTOCARPUS Mertensii. — Fronds much tufted, long, slender, and cylin- 

 drical, very distantly pinnated or occasionally bipinnated ; pinna) opposite, 

 everywhere be^et with close, distichoiis ramuli, in the middle of which 

 are immersed elliptical binate spores. 



EcTOCAKPUS Mertensii. — Ag. Sp. Alg. vol. ii. p. 47; Hoolc. Br. Fl. vol. ii. p. 327; 

 Wyatt, Alg. Danm. Fo. 130; Endl. 3rd Suppl. p. 21 ; Ilarv. P. B. 

 plate 132; Harv. Man. p. 62; Harv. Syn. p. GO; Atlas, plate 22, 

 fig. 96 ; /. G. Agardh, Sp. Gen. Alg. vol. i. p. 20. 



.Conferva Mertensii. — B. Bot. t. 999 ; Dlllw. Conf. Suppl. p. 79. 



Hab. — On mud-covered rocks and stones from low-water mark to four fathoms. Annual. 

 April to June. Not common ; but generally distributed round all our coasts. 



Geogr. Dist. — British Islands ; Atlantic shores of France. 



Description. — Fronds densely tufted, occasionally slightly entangled, 

 long, slender, and but sparingly branched, pinnate or bipinnate ; pinnae 

 and pinnules opposite, very unequal, a short and a long one often oj)po- 

 site, forming tufttj from four to sis inches or more in length ; the stems 

 and pinnse everywhere beset with distichous, spine-like, opposite, very 

 unequal ramuli, a pair generally arising from the summit of each articu- 

 lation ; they are short, scarcely tapering, except at the apices, which when 

 young are piliferous, their middle swelling into an elliptical tubercle, 

 which contains immersed two roundish angular granules, or one trans- 

 versely biparted. Substance rather flaccid, and closely adhering to 

 paper. Colour, when j'oung, a fine rather dark olive green, changing to 

 a greenish brown, or at length to a yellowish brown when old. Articu- 

 lations in stem nearly as long as their diameter, becoming shorter 

 upwards, until in the pectinated ramuli they are several times shorter 

 than their diameter. 



"Tins charming plant, one of the rarest and most beautiful of the 



