Prof, de Notaris on Ginnania furcellata. 43 



the points which I have taken upon me to explain may have al- 

 ready been partially noticed by others, they appear to me never- 

 theless capable of further development and worthy of the renewed 

 attention of algologists. 



Most important observations on this species have been given 

 us by Agardh, Greville, Kiitzing and Montagne, but although 

 these authors have certainly illustrated in a masterly way the 

 form of the frond and fruit, they have not explained the struc- 

 ture with all those details which the present state of algology 

 requires. 



The elder Agardh, in his ' Species Algarum * (vol. ii. p. 212), 

 showed that the frond of Halymenia furcellata consisted of two 

 strata, the outer one membranaceo-fibrous, the inner one more 

 compact, united closely to the former by means of reticulated 

 fibres, from which the fructification is produced, consisting of mi- 

 nute punctiform tubercles, irregularly scattered and placed be- 

 neath the exterior membrane of the frond. Frons e duplici strata 

 componitur, exteriori membranaceo fibroso ; medullari compaction ; 

 utroque per fibras reticulatas conjuncto. Tubercula fructifera per 

 totam frondem irregulariter sparsa, minuta et punctiformia sub 

 membrana exteriori nidulantia. — Agardh, 1. c. 



Greville, to whom algology owes so many happy innovations, in 

 his ' Algae Britannicse/ pp. 163, 164, says : the fructification, in 

 fact, consists of a minute punctiform globules of seeds imbedded be- 

 neath the membranaceous coat of the frond, which is not perfo- 

 rated by any orifice : substance (of the frond) gelatinous and mem- 

 branaceous, the cavity filled with a pellucid semifluid mass and a 

 fine network of delicate filaments ;" as would naturally result from 

 a cord of fine filaments covered with a membranaceous sheath 

 independent of them. 



These definitions are too diffuse and incomplete, and their in- 

 sufficiency is immediately apparent if we contrast them with the 

 descriptions given a short time since by the celebrated D. Zanar- 

 dini in his f Synopsis Algarum in Mari Adriatico hucusque de- 

 tectarum' (Memorie della R. Accademia delle Scienze di Torino, 

 serie 2. torn. iv. p. 124), and by Montagne in his most interest- 

 ing Cryptogamic Flora of the Canaries (Histoire Naturelle des 

 lies Canaries, torn. iii. 2nde partie, p. 162), who, availing himself 

 of the particular characters of the fruit, which I believe he was 

 the first to describe correctly, has proposed to make this species 

 a new genus under the name of Ginnania. 



The facts which Zanardini mentions would indeed have but 

 slight connexion with the matter before us, having been suggested 

 by the analysis of the frond of the variety cartilaginea from the 

 Adriatic (Syn. Alg. &c. /. c), — which, according to the observa- 

 tions and specimens with which Professor Meneghini has kindly 



