Ser. Melanospeemrj:. Pam. Ectoearpea. 



Plate CXXXII. 



ECTOCARPUS MERTENSII, Ag. 



<• ex. Char. Frond capillary, jointed, olive or brown., flaccid, single-tubed. 

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

 borne on the raoiuli, or imbedded in their substance. Ectocakpus 

 [Ly)ifjh.\ — from euros, external, and napiros, fruit. 



Ectocakpus Mertensii ; distichous ; branches opposite, of unequal length, 

 linear, mostly undivided, closely set, throughout their whole extent 

 with slender, subulate, opposite ramuli; joints of the stem longitudi- 

 nally striate, transparent, with a central coloured band, rather shorter 

 than their breadth; spores binate, imbedded in the ramuli. 



Ectocarpus Mertensii, Ag. Sp. Alg. vol. ii. p. 47. Hook. Br. Fl. vol. ii. 

 p. 327. Wyatt, Alg. Damn. no. 130. Hare. Man. p. 43. Endl. 3rd 

 Suppl. p. 21. 



Conferva Mertensii, E.Bot. t. 999. Dillw. Conf. Suppl. p. 79. 



Hab. On mud covered rocks and stones, near low-water mark and at a 

 greater depth. Annual. April and May. Rare; but pretty gene- 

 rally distributed. Yarmouth, Mr. Wigg. Coast of Durham, Mr. II . 

 Backhouse. Torbay, Mrs. Griffiths. Salcombe, very line, Mrs. 

 Wyatt. Sidmouth, Miss Cutler. Marazionand Dfracombe, Mr. Ralfs* 

 Mount Edgecumbe, Plymouth, Rev. W. S. Hore and Mr. Rohloff. 

 Bantry Bay, Miss Hutchins. Dredged in Strangford Lough, Mr. 

 II . Thompson. Howth, Dr. Coulter. Cove of Cork and Malahide, 

 IF. II II. Carrickfergus and Boundstone Bay, Mr. Ma' Cilia. 

 Orkney, Rev. J. II. Pollexfen. 



Geogr. Distr. British Islands. Atlantic shores of France. 



Descr. Fronds densely tufted, hut not in the Least matted together. Stems from 

 two to six, or more rarely twelve inches in length, nearly or entirely simple, 

 closely furnished from the base to the apex with distichous, opposite, erecto- 

 patent, lateral branches, which are of \ery unequal Length, Long and short 

 being indiscriminately mixed together. These primary branches are, in 

 large specimens, furnished with a second or third series, also very unequal 

 in lei mill, but uoneofthem Long, so that the general outline of the main branch 

 is narrow. Both primary and secondary branches are pectinated, at e\erv 

 joint, with a pair of opposite, subulate, patent ramuli, which in young 

 specimens terminate in a long, hair-like aeuinination, that drops off at a 

 later period of growth. Joints of the stem rather shorter than broad, with 



a central band ; those of the ramuli \erv manv times shorter than broad, 



each formed of several cellules. Spores immersed in the Bubulate ramuli 



about the centre, growing in pairs, separated b\ a transparent line, each 



spore of a half ellipsoid shape, dark olive. Colour, when young, a clear 

 brown olive, becoming foxy when old, and acquiring a greenish Bhade, if 

 dried after some steeping in fresh water. Substance flaccid. The plant 

 closely adheres to paper. 



