288 MISS SARAH M. BAKER ON THE 
specimens, no single male receptacle has been found. Italso bears no vesicles. 
Sauvageau has very fully discussed the affinities of his F. lutarius *, and 
decided that it was originally derived from F. spiralis | (F. platycarpus, 
Thur.), the hermaphrodite species with projecting paraphyses and no vesicles, 
the antheridia having been graduallv reduced to nil. Не suggested that the 
Fic. 8. 
Frond of Fucus volubilis from Blakeney Point, bearing receptacle. х 2. 
vesicled English form, as also the Spanish one, was derived from 7. vesicu- 
losus, diceious with non-projecting paraphyses; but was unable to decide 
with certainty, because no receptacles had been described. This surmise 
seems to be amply borne out by the nature of the conceptacles found, It is, 
at any rate, pretty obvious that these two almost identical plants cannot 
* Bord. Soc. Se. Arc., Trav. Lab. 1908, p. 137. 
T Borgesen, in Journ. Linn. Soc., Bot. vol. xxxix. (1909) p. 105. 
