377 



Order CERAMIACEAE. 

 GRIFFITHSIA C. Agardh. 



48. G. setacea (Eli.) Ag. 



In July 1899 I found in Trangisvaagfjord opposite Tværaa (Syd.) 

 in abont 10 fathoras of water a large vigorous, but sterile speeimen, 

 associated with other Florideæ. 



Landl 1. c. p. 233 reports Conferva (Griffithsid) corallina Lightf.) 

 Ag. Ironi the Færoes, but as this species has not been found since it is 

 possible tliat it was a confusion with the above-mentioned species. 



CALLITHAMNION Lyngb. 



49. C. scopulorum Ag. C. Agardh, Species Algarum, Vol. II, p. 166; 

 J. Ag., Spec. Alg., Vol. 2, pars 1, p. 47; Callithamnion roseum § tenue 

 Lyngb., Hydrophyt., p. 126, tab. 39. 



In order to ascertain the relationship between this species and 

 C. roseum with which I at first thought it to be most closely allied, 

 I compared my material of C. scopulorum — which exactly agrees with 

 Lyngbyes material ol' what he calls Callithamnion roseum (3 tenue 

 with the specimens labelled C. roseum in the Herbarium of the 

 Botanical Museum in Copenhagen, especially with No. 162 in Le 

 Jolis's Alg. mar. de Cherbourg and No. 703 in Phykotheka univer- 

 salis, and I came to the conclusion that while my material bore no 

 great resemblance to the former it approached closely to the latter. 

 In faet these two algæ which are here given under one name diller 

 so widely from each other, even on a cursory examination that one 

 is led to suppose that there must have been a confusion of two 

 distinct species ; and as out museum with regard to these species is not 

 rich in specimens for comparison, and more particularly as it does 

 not contain specimens, excepting Le Jolis's, on the determinations of 

 which I could quite rely I wrote to Dr. E. Bornet of Paris for bis 

 opinion and cannot do better than quote what he very kindly writes 

 tome: — »Je n'ai jamais vu d'échantillon authentique de Ceramium 

 roseum Roth, Catalecta botanica, II, p. 183, et je ne saurais, d'aprés la 

 description, reconnaitre l'espéce, dont il s'agit. Mais si vous consultez 

 l'English Botany, tab. 966 et Dillwyn, p. 17, vous verrez que c'est 

 Roth lui-méme qui anommé les exemplaires récoltés par Sowerby 

 et qui sont représentés dans ces deux ouvrages. Or Dillwyn 

 mentionne la particularité suivante: »branches are repeatedly sub- 

 divised, so that as they approach the summits, they have a very 



