O *r»^< 





The limitation proposed in Norw. Lithoth. 1 ) of the Norwegian 

 unarticulated calcareous algae, and in consequence of the majority 

 of the boreal-arctic calcareous ones, was in part altered most re- 

 cently in Rev. Syst. Surv. Melob. 2 ). The fact is that several species, 

 classified as independent ones, turned out to vary more than it 

 appeared from the material I then possessed, and could not, there- 

 fore, be maintained as independent. Besides I had partly laid too 

 great stress on the shape and the size of the conceptacles, as even 

 these may vary more than then presumed. Be it said that by far 

 the greater part of the material in hand consisted of sterile specimens 

 or of specimens with conceptacles but slightly developed. 



Shortly before composing the Rev. Syst. Surv. Melob. I had 

 myself gathered new, large material along the northern coast of 

 Norw r ay, and besides I had received more material from other 

 arctic or boreal areas. I had not then, however, as is evident 

 only from the queries added to some of the species or forms 1. c, 

 the opportunity of a complete revision particularly of the species 

 belonging to the genus Lithothamnion which form the bulk of 

 the calcareous algae here occurring. What principally prevented 

 such a complete revision was the fact that I still wanted sufficient 

 material from the south-western and the southern parts of the coast 

 of Norway. Such material, however, has been collected of late 

 years, which has to a great extent contributed to the understanding 

 of not only several of the arctic or subarctic Lithothamnia, but 

 also of some boreal ones. 



v ) M. Foslie. The Norwegian Forms of Lithothamnion. — Det Kgl. norske 

 Videnskabers Selskabs Skrifter 1894. Trondhjem 1895. 



-i M. Foslie. Revised Systematical Survey of the Melobesieae. — Det Kgl. 

 norske Videnskabers Selskabs Skrifter 1900 no. 5. Trondhjem 1900. 



