44 Prof, de Notaris on Ginnania furcellata. 



favoured me, must be referred to Nemostoma dichotoma, — were it 

 not that the error into which Zanardini was drawn in considering 

 with Agardh (Spec. Alg. /. c.) Nemostoma dichotoma as a variety 

 of Halymenia furcellata, proves the close analogy of structure 

 which subsists between the two species in question, and this 

 analogy is of itself sufficient to substantiate the inexactness above 

 alleged. 



Neither, in the ' Algse Maris Mediterranei et Adriatici ' (pp. 95, 

 96) has the celebrated J. Agardh described Halymenia with 

 greater precision under the following characters : — From filis in- 

 terioribus varie intertecctis versus superficiem in cellulas rotundatas 

 anastomosantes, extus cellularum granulosarum strato scppe tectas 

 abeuntibus, constituta. Fructus duplex ? Favellidia infra stratum 

 externum nidulantia, frondis dissolutione elabentia (?) intra peri- 

 sporium arctissime circumdans tenacissimamque congeriem spora- 

 rum obovatarum foventia. Spharosporce .... Terms which are 

 perhaps not quite applicable to all the species of the genus, and 

 still less to our plant, which is scarcely at all indicated. Besides 

 which, a serious omission is to be imputed to him in not having 

 noticed, perhaps deliberately, the observations published on the 

 subject by Montagne; and although I allow that he might 

 not be able to adopt his views, yet at any rate he was bound 

 to cite them, either to discuss their merits or show their in- 

 consistency. 



Montagne, as I said before, has described the structure of the 

 fruit with great exactness, which really incloses nuclei composed 

 of slender radiating sporiferous threads. Nucleus e filis constat 

 articulatis numerosissimis quoquoversum irradiantibus in articulo 

 quorum extremo sporidium oblongum gigartoideumve continetur. 

 Membrana tenerrima tenuissime punctulata, diaphana, ad maturi- 

 tatem fructus massamfilorum investit ; but with regard to the frond, 

 when he says — intus filamentis constans intricatis, hyalinis, e ceU 

 lulis periphericis membrana corticalis, ut videtur, oriundis, vet sal- 

 tern ad easdem spectantibus — he either knew not how to draw the 

 characters, or has not expressed himself with the necessary clear- 

 ness. 



Lastly, Kutzing in his recent and admirable publication, ' Phy- 

 cographia Universalis/ has also made Halymenia furcellata a new 

 genus with the name of Myelomium, denned in the following 

 terms : — Phycoma filiforme lubricum, dichotomum, solidum, ex 

 stratis tribus formatum, corticate crassiusculo subparenchymatico, 

 intermedio laxe fibroso, medio ex fibris parallelis longitudinalibus 

 numerosis dense conjunctis compositis. Of the fruit no notice is 

 taken. However censurable such slightly framed generic cha- 

 racters may be from any one, it fills one with astonishment to see 

 how some authors allow themselves to be governed by the mania 



