Page:Transactions of the Linnean Society of London, Volume 6 (1802).djvu/162

rzS Mr. Turner's Defcnpt'iom of which they effentlally difFer, I fhould ftill have felt very unwilling to defcribe them as fpecifically diftindl, were it not for the curious lines of concatenated veins which I find both peculiar to this species, and conftant in all the fpecimens that have fallen under my obfervation. In a frefh ftate thefe veins are fo eafily vifible, as to give the plant a ftriated appearance i but when dried, efpecially if fastened upon paper, a good glafs and ftrong light are neceffary to discover them. I have never been able to form a fatisfaftory opinion upon the office which they are intended to perform in the internal organization of the fpecies; nor indeed is this a fubjeil upon which, in our prefent knowledge of the marine algae, it would be right to hazard a conjedlure. I fhall therefore content myfelf with obferving, that they run from the midrib to the fides of the leaf generally in parellel lines, but fometimes branching and anaftomofing; that they arc quite pellucid; and that they are interfcfted at regular diftances with joints, like the filaments of Conferva:. The colour of Fucus rufcifalius is always much darker than that of Fucut Hypogloffum', the leaves of a different form, and, particularly when young, very blunt; the texture of the membrane, under a powerful microfcope, diffimilar; the ftem far ftronger; and the midrib more prominent as well as more vifible: to which is to be added, that the months of January and February are thofe in which this plant bears its fruit, and in which it is mofl: frequently feen upon the Yarmouth beach; wliereas Fucus Hypogloffum fruftifies only in the fummer, and never appears at any other part of the year. Hence I conclude, that the one is annual, the other perennial. I have a fpecimen oi Fucus rufcfdius with the root completely fibrous; no tendency to which I ever faw in Fucus Flypoglojfum; but, this not appearing to be always the cafe, Ihave not confidered afingle inftan.ce fufficiently important to ground any part of the fpecific diftinclion upon it. In the mode of fructifying, the two plants completely agree; and, a.s much