42 ON THE GENERA ANADYOMENE AND MICRODICTYON. 
Edward Bennett and I, purchased all the ** Mousse de Corse?" we could 
find in London, and searched it most industriously, but without effect. 
I was therefore greatly pleased when, many years after, Professor 
Harvey most kindly gave me a series of the species he had found in 
Florida, which I could study at my leisure, and I found it as beautiful 
as I had anticipated. 
Having recently had occasion to examine the specimens of the 
genera Anadyomene and Microdictyon, in the botanical collection of the 
British Museum, 1 was much interested in two specimens which were 
collected by my very kind friend, Mr. Archibald Menzies, in the Gulf 
of Mexico, in the year 1802, which appear to this time to have been 
undescribed. One is allied to, but very distinct from, the genus Anadyo- 
mene of Lamouroux, and is a giant of the tribe. The other is allied to 
Microdictyon, a genus established by M. Decaisne, but differs from 
it in the frond being free, and on a filiform conferva-like branched 
stem, the leaf-like frond bearing a resemblance to the frond of Struvea 
of Sonder and Harvey. 
The Anadyomene has long been known; it was figured by Dillenius ; 
Wulfen described it as an Ulva, and the genus was established by M. 
Lamouroux as a zoophyte, from some specimens which he found in the 
“ Mousse de Corse” in the stock of a druggist in Normandy. Tt is 
now well known to be an Alga. 
The form and structure of Microdictyon was well described and 
figured by Colonel Velley in 1799, and his figure is the best, except 
Harvey's, that we yet have ; but he referred it to Conferva—that maga- 
zine for the articulated Alga. 
Professor Endlicher, in the third supplement to his ‘Genera Plan- 
tarum,' formed the genus Anadyomene into a subtribe, under the name 
Anadyomenea, p. 18. 
Kützing, in his ' Species Algarum,’ 1847, forms of the genera Ana- 
dyomene and Microdictyon a family, under the name of Anadyomenee, 
p- 371, referring to it the genus Talarodictyon of Endlicher, but with 
doubt. I do not know the latter genus ; indeed, it is only described 
from a figure in the MS. of Tilesius, 
. Professor Harvey, in his very useful ‘Index Generum Algarum,’ 
1860, refers the genera Microdictyon and Anadyomene with Struvea, as 
genera of the family Valoniacea, p. 13. 
There can be no doubt that the two genera belong to two very dis- 
