21' M. FOSLIE. REV. SYST. SURVEY OF MELOBESIEAE. [1899 No. 5] 



D. macrocarpum f. Laminariae (Crn.) Fosl. 



3. D. hapalidioides (Crn.) Fosl. 



f. typica. (incl. Melob. simulans Crn.) 

 f. confinis (Crn.) Fosl. 



4. D.? adplicitum Fosl. (D. hapalidioides f.?) 



5. D. ? prototypus Fosl. 



Gen. Choreonema Schm. 



Thallus parasitical, the hypothallic cells as rhizoids penetrate 

 the tissue of other calcareous Algæ. 



Conceptacles of sporangia superficial, conical, with an apical 

 pore; sporangia arising from a plain disc. 



Conceptacles of cystocarps superficial, conical (smaller than 

 the former), with an apical pore; carpospores arising around the 

 periphery of the „conjugation cell", the central parts of the latter 

 with a bundle of short paranemata. 

 1. Ch. Thureti (Born.) Schm. 



