Ko. 7] REMARKS ON MELOBESLE IN HERBARIUM CROUAN 13 



co7tfi7iis, however more because of the habit than owing to other 

 characters. The specimens of f. confinis which stick to Gelidium 

 are much lighter than the typical form, of a greyish colour with 

 a purplish shade, nearly according with the said form on loose 

 substratum, but this is probabh' only due to local conditions. It 

 spreads itself to Gelicliam probably from the shells of Balanides 

 which it in part also covers, the shells forming a part of the sub- 

 stratum of the said species. Such shells are to be found together 

 with all the tufts of Oelidimn that I have seen infested with the 

 present alga. The form confinis partly surrounds the branches of 

 the said host partly and more frequenth' only the half of the cir- 

 €umference of a branch, but often in its whole length, or stretches 

 itself between the densely crowded and little hy little almost de- 

 cumbent branches, so that it at length nearly covers a tuft of 

 the host. 



In structure it agrees in the main with the typical form, and 

 also as regards the conceptacles of sporangia. 



Melobesia Laminariæ Crn. 

 Fl. Finist. p. 150. 



= Dermatolithon Laminariæ (Crn.) Fosl. mscr. et Litho- 

 phyllum Crouani Fosl. 



In Some new or er. Alg. p. 17 I recorded an alga b}^ the 

 name of Lithophyllum Crouani, in part included in D. Laminariæ, 

 such as the latter has been apprehended by French algologues after 

 Crouan. Judging from some small authentic crusts afterwards 

 seen, it appears that both species also have been included by him, 

 though the description 1. c. in the main refers to the present spe- 

 cies. However, the crusts are sterile and then the said two species 

 sometimes are not easy to separate especially in a dried state, but 

 at least one of them must be referred to L. Crouani, a species 

 which nearly always grovvs in company with D. Laminariæ, but 

 on the whole more scarce than the latter. This spesies is closely 

 related to D. liaioalidioides. 



A calcareous alga from the Faroe Islands mentioned b\' 



