See. MELANOSPERMEtE. ( 119 ) Fam. CHORDARIEvE. 



LEATHESIA BERKELEYI.— S^am 



Gen. Char. — Frond cellular, fleshy, more or less globose ; cells of the central portion 

 cylindrical, arranged in radiating dicbotomous series ; those of the outer portion 

 forming tufted, club-shaped, moniliform filaments. Fructification : obovate spores, 

 produced at the bases of the apical filaments. Name in honour of the Rfiv. 

 Gr. R. Leathes. 



Leathesia Berkeleyi. — "Fronds dark brown, depressed, fleshy, solid, 

 filaments densely packed." 



LvikTSESih. BerTceleyi. — Harv. P. £. plate 176; Harv. Man. p. 48; Earv. Syn. 

 p. 42; Atlas, plate 15, fig. 59; /. G. Agardh, Sp. Qen. Alg. vol. i. 

 p. 51. 



Ch^tophora Berkeleyi. — Grev. in Berk. Gl. Alg. t. 1, fig. 2; Harv. \n Hook. 

 Br. Fl. vol. ii. p. 390 ; Wyatt, Alg. Damn, No. 231 ; Harv. Man. 

 1st edit. p. 123, 



Hab, — On submarine rocks between tide-marks. Annual. Summer. Torquay {Re^'. 

 J. M. Berkeley) ; Tor Abbey Rocks {Mrs. Wyatt) ; rocks at Kilkee, Co. Clare 1833, 

 Miltown Malbay and Valentia, Kerry {Dr. Harvey). 



Geogr. Dist. — South of England and West of Ireland. 



Description. — Fronds somewhat convex or subhemispherical, spread- 

 ing, from one to two inches in diameter, from a quarter to half an 

 inch in thickness, roundish when yomig and more or less smooth, 

 more irregular when old, and the fronds frequently confluent. Struc- 

 ture cellular, cells of the central portion oblong, cylindrical, arranged 

 in the form of dichotomous hyaline filaments; those of the middle 

 stratum forming dichotomous, moniliform, coloured filaments, those of 

 the periphery deeply coloured, tufted, moniliform ; all densely packed, 

 forming a solid frond at all stages of its gi-owth. Substance rather 

 fiiTa and cai'tilaginous, and partially adhering to paper. Colom-, a dark 

 olive brown. 



Of this singular little plant we have only seen dried specimens, 

 kindly communicated by Professor Dickie and others. 



It is said to be abundant at least in several places on the south- 

 western shores both of England and Ireland, but we have not heard 

 of its occurrence on those of Scotland. It is possibly confined to those 

 places whose vegetation seems influenced by the temperatm-e of the 

 Gvdf stream, and where many others of our rarer species of Alga) 

 have been observed. 



