Bibliographical Notices. . 213 



better suited to the task, both in regard to his having been of late 

 years the chief describer of the collections of Algae brought to this 

 country from all quarters of the globe, and to his study of the living 

 plants in a subtropical as well as a temperate climate. At p. 15 of 

 the Introduction we have the personal observation of the author on 

 the Sargassum or " Gulf- weed." He remarks : — 



<l I have made the voyage three times, and only once met with sea-weed 

 in sufficient quantity to claim any attention. It did not then occur in strata 

 resembling fields, but rather in ridges, from ten to twenty yards broad and 

 of great length, stretched across the sea. The species invariably found in 

 these was S. bacciferum. Of a large quantity that we dredged up for se- 

 veral successive days, not a particle belonged to «S". vulgare ; and I am much 

 inclined to suspect that most, if not all, of the stories related by voyagers as 

 of that species, belong to S. bacciferum, a plant which has never been found 

 in any other situation than floating about in the deep sea ; whereas S. vul- 

 gare (the Fucus natans of Turner) is well known in many tropical countries 

 to grow on the rocks, within the reach of the tide, like others of the genus. 

 It is therefore much to be regretted that the name of natans was not re- 

 tained for *S\ bacciferum, to which it is chiefly, if not only, applicable. 

 Authors who have written on this Fucus have much disputed, both respect- 

 ing its origin and whether it continues to grow whilst floating about. No- 

 thing at all bearing on the former question has yet been discovered ; for 

 though species of Sargassum abound along the shores of tropical countries, 

 none exactly corresponds with S. bacciferum. That the ancestors of the 

 present banks have originally migrated from some fixed station is probable, 

 but further than probability we can say nothing. That it continues to 

 flourish and grow in its present situation is most certain. Whoever has 

 picked it up at sea, and examined it with any common attention, must have 

 perceived, not only that the plants were in vigorous life, but that new fronds 

 were continually pushing out from the old, the limit being most clearly de- 

 fined by the colour, which in the old fronds is foxy-brown, in the young 

 shoots, pale, transparent olive. But how is it propagated? for it never pro- 

 duces fructification. It appears to me that it is by breakage. The old 

 frond, which is exceedingly brittle, is broken by accident, and the branches, 

 continuing to live, push out young shoots from all sides. Many minute 

 pieces that I examined were as vigorous as those of larger size, but they 

 were certainly not seedlings, and appeared to me to be broken branches, all 

 having a piece of old frond, from which the young shoots sprung. As the 

 plant increases in size it takes something of a globular figure, from the 

 branches issuing out in all directions as from a centre. On our own shores 

 we have two species analogous to S. bacciferum in their mode of growth, 

 namely, Fucus Mackayi, and the variety (S. sub-costatus of Fucus vesicu- 

 losa (F. balticus, Ag.). Neither of these has ever yet been found attached, 

 though they often occur in immense strata ; the one on the muddy sea-shore, 

 the other in salt-marshes, in which situations, respectively, they continue to 

 grow and flourish ; and it is remarkable that neither has ever yet been found 

 in fructification, in which respect also they strikingly coincide with S. bacci- 

 ferum. And if it be hereafter shown that F. Mackayi is merely F. nodosus, 

 altered by growing under peculiar circumstances, may it not be inferred that 

 S. bacciferum — which differs about as much from S. vulgare as F. Mackayi 

 does from F. nodosus — is merely a pelagic variety of that variable plant 1" 



That Fucus Mackayi is a legitimate species, or anything more than 

 a remarkable variety of F. nodosus, we never could believe, and have 

 been further strengthened in this opinion by finding near one of the 



