230 FLORA OF MOUNT DESERT. 



CERAMIACE^. 



CERAMIUM, Lyngb. 



C. Hooperi, Harv. 



Common on overhanging rocks near low-water mark. Near 

 Seal Harbor (Collins); — Sea Wall (Holden). 



C. rubrum (Huds.), Ag. 



Common everywhere (Collins) ; — Sea Wall (Holden). 



ANTITHAMNION, Naeg. 



A. Pylaissei (Mont.), Farlow. CaUlthamnion Pylaiscei, Far- 

 low's Manual, 123. 

 On Ptilota pectinata (L. E. Boggs). 



PLUMARIA, Stack. 



P. elegans, Bonnem. Pt'dota elegans, Farlow's Manual, 133. 



On overhanging rocks near low-water mark. Near Seal Har- 

 bor (Collins). 



PTILOTA, Ag. 



P. pectinata (Gunner), Kjellm. P. serrata, Farlow's Manual, 

 oo. 

 Common; cast up from deep water. Seal Harbor, and else- 

 where (Collins); —Sea Wall (Holden). 



RHODOCHORTON, Naeg. 



R. Rothii (Engl. Bot.), Naeg. Callithamnion Rothil, Farlow's 

 Manual, 121. 

 Common on rocks near low-water mark. Seal Harbor, and 

 elsewhere (Collins); — Greening Island (Holden). 



R. membranaceum, ]\ragnus. 



A minute species, growing in Polyzoa, sponges, etc. ; the fila- 

 ments forming a more or less dense network, sometimes entirely 

 tilling the interior of the host, which is then quite noticeable, 



