320 



ought to give a yellowish and then rusly-red reaction of medulla 

 and soredia, do not do so at all and must consequently be referred 

 to R. farinacea, also by those who give importance to chemical 

 reactions as specific characters. 



19 (a). Stereocaulon coralloides F^r. 



Here and there, in crevices, on rocks and pebbles, but weakly de- 

 veloped (R., !). 



20 (b). S. denudatum Fik. and var. pulvinatum Schaer. 



On pebbles and gravelly ground, very comnion; the specimens often 

 very low, 1—2 mm. only (R., !). 



21 (c). S. tomentosum Fr. 



On gravelly ground, here and there (R., !). 



Var. alpinum (Laur.). 



As above. Sydero: Præstefjæld (R.). 



22 (d). S. paschale (L.). 



As above. Rordo: Helgefjæld; Stromo: Navnefjæld (!). 



23. S. cereoHnum Ach. 



On boulders. Nol so (R.); Stromo: Sandegærde (R.). 



24 (a). Cladonia gracilis (L.). 



On gravelly and peaty ground. Here and there (R.. !). 



25 (b). C. alcicornis (Lightf.). 



On heath. Bord 6: Gerdumrejn (!); Stromo: Flojvig (!); Sydero: 

 Kvalvig (!). 



The laciniae attain a centim. in length, and occur more fre- 

 quently with apothecia than the other phaeocarpous Cladoniae of 

 the Færoes. 



26 (c). C. cervicopnis Ach. 

 Perhaps the most common (R., !). 



In the specimens from Trangisvaag (!) the leaves are turgid, 

 almost bladdery, probably a monstrosity. The Færoese specimens 

 give no yellow reaction on application of hydrate of potash and in 

 Nylander's nomenclature they are to be cailed C. sobolifera Del. 



27 (d). C. decorticata (Fik.). 

 Here and there (R., !). 



C. degenerans and its var. lepidota (Færoernes Flora p. 94) I refer 

 to this type. 



28 (e). C. pyxidata (L.). 



Very common on rocks aniong mosses and on the ground (R., !). 



