368 ACCOUNT OF SOME OF THE 



Genus has been constituted by Olivi, under the 

 name of Lamarkia, with the following character : 

 L. stirps radicata sub-coriacea mollis, composita 

 utriculis in ax'im yerpendicularibus. The na- 

 ture of the frond in F. membranaceus, would not 

 lead any one to expect a root of so dissimilar a 

 structure ; yet if we consider the many anomalies 

 in the vegetable kingdom, such an occurrence ap- 

 pears far from impossible. 



(10.) Fucus laciniatus. 



A curious circumstance has been observed by 

 Mrs Griffiths respecting this Fucus, which places 

 it among those species which bear two kinds of 

 fructification. In the common mode of fructifica- 

 tion in Fucus laciniatus, the seeds are contained in 

 tubercles situated in the marginal processes ; but 

 many instances occur where these processes are en- 

 tirely wanting, and it is in such cases that Mrs 

 Griffiths has remarked a narrow line of a darker 

 colour than the rest of the frond, to be continued 

 along the whole margin. This line, under the mi- 

 croscope, is evidently formed by very minute seeds, 

 apparently single, and immersed in the substance 

 of the frond. This mode of fructification Mrs 

 Griffiths has found to take place in many hundred 

 plants that she has examined. I have since obser- 

 ved the same arrangement, and I have many in my 

 possession presented to me by her, as well as many 



