DR. DICKIE ON AECTIC SPECIES OP ALG.E. 241 



Melohesia polymorj^ha, L. I possess fresh shells of MjjtiJus 



edulis completely encrusted Avith this species ; flat stones from 



the same locality present a similar crust at the edges, in the 



centre rising into rounded dichotomous obtuse branches an inch 

 to an inch and a half long, resembling j\L calcarea. The two 



species are probably identical. In these Arctic specimens the 

 motion of the valves, though limited, and the brancln'al currents 

 of the living animal may prevent full develoi^ment, which pro- 

 gresses on the stone in the absence of any disturbing cause* 



Dehsseria sinuosa^ Ag. Has been found in lat. 75° N*. 



lllwclopliijllis vejyrecttla^ J« Ag. I possess specimens of this 

 from Whale-Fish Inlands. 



I'liyUopliora xnterrv'j)ta^ Grev. This remarhable and rare Ahja 

 was placed originally in the genu?< Hlwdijmenla, rruitiug spe- 

 cimens have been brought home by the late Swedish expedition to 

 Spitzbergen, and Professor J. Gr. Agardh has thus been able to 

 prove it to be a true Flnjllcplora, allied to P. Brodim, the fruit 

 being disposed nearly as in that species. 



Ceramium rtilnon, Ag., var. d, virgattnn. 



TJlva I nil OS a ^ L. 



Viva cris2yaj Liglitf. 



Porpliyra vulgaris, Ag. 



Speclu^ens in my collection from the north extremity of Pavia 



Straits are small, not exceeding two inches. 

 CladopJiora rupesfris, Kiitz. 

 Chatomorplia Piq_uotiana, Mont. 

 Jlormotriclixim CarmicJicelii, Harv. 

 -ff. loreahj Harv. 

 II, WcrmsJcioldii, Kiitz. 

 2Iongeotia (species doubtful). 

 Oscillatoria Corium, Ag. 

 JS'ostoc muscorum^ Yauclier. 

 Nostoc micvoscopicum, Carm. 



r 



^osfoc verrncosumy Vaucher. 



