THE MARINE AI.GJE OF THE OBAN DISTRICT. 237 



Ptilothamnion pluma, Thur. {Callithamnion pluma, 

 Phyc. Brit.). — "On Laminaria hyperhorea at Appin" 

 (Carmichael). 



Qriffithsia setacea, C. Ag. — Common on islets off 

 Lismore, at low water. 



Pleonosporium Borreri, Nag.— One specimen was 

 obtained from a rock-pool at low water, near the 

 Falls of Lora. 



Hhodochorton Rotliii, Nag. 



Rh. floridulum, Nag. 



Rh. membranaceum, Magn. 



All three species are common in the district. 



Rh. sparsum, Kjellm. (Callithamnion sparsum, 

 Phyc. Brit.). — "Appin" (Carmichael). 



Rh. mesocarpum, Kjellm. {Callithamnion meso- 

 carpum,, Phyc. Brit.). — "Appin" (Carmichael). 



Callithamnion Hookeri, C. Ag. 



C. corymbosum, Lyngb. 



I was rather astonished at the paucity of Calli- 

 thamnions on the coast ; these two species were the 

 only forms I saw. 



Plumaria elegans, Bonnem. 



Ptilota plumosa, G. Ag. 



Both common forms in Loch Etive and elsewhere. 



Ceramium strictum, Harv.— I am doubtful about 

 the identification of this species, of which I found 

 only one plant. 



C. rubrum, C. Ag. — Abundant and variable as 

 usual. 



C. acanthoaotum, Carm. — Occasionally at low 

 water near Dunstaffnage. 



C. Deslongchampsii, Chauv.— Fairly common in 

 Loch Creran and on islets off Lismore. 



Cohort V. — C BYPTONEMIN^. 



Order I. — Glceosiphoniace^. 



Gloeosiphonia capillaris, Carm. — " Appin, low 

 water" (Carmichael). Loch Etive, opposite Achnacree. 



