799 



As to the 111 Færoese species wanting at Greenland, they are 

 mostly species also wanting at Iceland (namely the 54 species men- 

 tioned as belonging to group III and group IV p. 793 — 94), and in 

 addition the following 57 species: Porphijra coccinen, Chantransia 

 Alariæ, Chondrns crispiis, Gigartina mamillosa, PhijUophora mcmbra- 

 nifolia, Ahnfeltia plicata, Cystocloniiim purpur ascens, Lomentaria rosea, 

 L. ckwellosa, Plocamiiim coccineiim, Delesseria alata, D. sangiiinea, 

 Polysiphonia fastigiata, P. nigrescens, Pterosiphonia parasitica, Odon- 

 thalia dentata, Callithamnion arbnscula, C. scopulorum, Plumaria ele- 

 gans, Ptilota phimosa, Ceramiiim acanthonotiim, Diimontia fdiformis, 

 Cnioria pellita, Phijmatolithon polijmorpimm, Lithothamnion Lenor- 

 mandi, Lithophyllnm Croiiani, L. macrocarpiim, Corallina officinalis, 

 Petroderma maculiforine, Mijrionema vulgare, M. Corunnæ, M. færoense, 

 M. speciosum, Ectocarpiis tomentosns , E. fasciculatiis , E. Hincksiæ, 

 Phæostroma parasiticum, Dictyosiphon Ekmani, Desmarestia ligulata, 

 Leathesia difformis, Laminaria færoensis, L. hyperborea, Fiicus spiralis, 

 Peluetia canalicidata, Codiohim pnsilhim, Enteromorpha Linza, E. cla- 

 ihrata, Prasiola fiirfiiracea, P. stipitata, Acrochæte repens, A. albescens, 

 Dermocarpa Farlowii, Hyella endophytica, Phormidiiim antnmnale, 

 besides the 3 referred only to the genus. These 111 species are 

 almost all of a more southern distribution and belong to the warm- 

 boreal and cold-boreal groups. 



As to the 65 species found at Greenland and not at the Færoes, 

 they can be referred to the following groups: 



The arctic group: Ceratocolax Hartzii, Callymenia sanguinea, 

 TurnereUa Pennyi, Delesseria Baerii, D. Montagnei, Polysiphonia arctica, 

 Dilsea integra, Petrocelis polygyna, Cruoria arctica, Lithothamnion 

 foecundum, Ectocarpus pycnocarpus, Omphcdophyllum ulvaceum, Kjell- 

 mania subcontinua, Coelocladia arctica, Dictyosiphon corymbosum, 

 Myriocladia callitricha, Laminaria solidungula, L. cuneifolia, L. groen- 

 landica, L. nigripes, Monostroma groenlandicum, M. leptodermum, Ulo- 

 thrix scutata, Arthrochæte penetrans, Chætobohis gibbus, Urospora 

 crassa; 26 species in all. 



The subarctic group: 



Subdivision 1 : Peyssonnelia Rosenvingii , Lithothamnion tophi- 

 forme, Ralfsia ovata, R. deusta, Myrionema Laminariæ, Ectocarpus 

 helophorus, E. ovatus, Sphacelaria racemosa, Phæosaccion Collinsii, 

 Symphyocarpus strangulans, Delamarea attenuata, Coilodesme bulligera, 

 Dictyosiphon hispidus, Saccorhiza dermatodea, Laminaria longicruris. 



