THE URYOPHYTA OF ICELAND 443 



but the specimens in the Botanical Museum are wrongly determined; 

 most af them must be referred to D. Starckei or D. angiistiim. 



Dicmmim mollc usually grows on damp gravelly ground on moun- 

 tain heights. In NW. Iceland it is one of the most commonly occurring 

 mosses on rocky flats, and is common down to about 200 metres above 

 sea-level; but also frequently descends as far down as the bottom of 

 the valley. It grows both on gravelly flats soaked by melting snow 

 and on damp slopes; also on lower levels on heathy soil, with other 

 Dicramim spp. (D. scopurium and D. fuscescens), among Vitcciniiim, Em- 

 pi' t mm, etc., in large tufts which are usually closely interwoven with 

 Lophozia lycopodioides , L. Knnzeana, L. quinquedentata, L. Floerckei, L. 

 uentricosa and other Hepaticas. Near Modruvellir it grew partly on damp 

 gravelly ground, partly intermixed in abundance in Rhacomitrium hyp- 

 /loiY/fs-heaths; in this latter locality also it was mixed with Lophozia spp. 



In lava-fields it usually grows in company with D. Starckei, commonly, 

 as for instance in the clefts near Thingvellir, in cushions as much as 

 10 cm. deep. The plants from the latter locality and from Hafnar- 

 fjordurhraun are sometimes not quite typical and approach so closely 

 to D. Starckei, that they can hardly be distinguished. The leaves are 

 sometimes orthophyllous, sometimes drepanophyllous. The fruit, which 

 is always present abundantly, ripens during July. In the district of 

 Isafjordur, however, ripe fruit was frequently found as early as in the 

 latter days of June. 



27. Dicranum Bonjeani de Not. 



D. palustre Br. eur. 



SE. Iceland: Hornafjordur!; Lon !. N. Iceland: near Eyjafjordur 

 (O. D.)!. W. Iceland: Dalasysla; Ketilstadr (H. J.)!; Reykholtdafur (Grl. !); 

 Reykjavik!. 



The plants from all the above-mentioned localities agree exactly 

 with D. Bonjeani, but being quite sterile they cannot be determined with 

 perfect certainty. Bog-forms of Dicramim scopariiim have often erect 

 leaves, slightly undulate at the apex, and are then extreme!}' difficult to 

 distinguish from D. Bonjeani. This species grows in bogs, usually on 

 knolls, and is common around Reykjavik and near Hornafjordur. 



Note. In several older lists Dicramim undnlatnm is enumerated as 

 found in Iceland by Morch and is also recorded by Gronlund from 

 Reykholt and Reykjavik, but all the specimens in the herbaria must 

 either be referred to D. scop a mm or D. palustre. 



28. Dicranum angustum Lindb. 



E. Iceland: Hornafjordur!; Berufjordur!; Lon!; Hof!. N.Iceland: 

 Myvatn (Grl.; determined as D. arcticu /??)!; Stadr near Hrutafjordur!. NW. 

 Iceland: Dynjandi!. W. Iceland: Stykkisholmur!; Reykjavik!. S. Iceland: 

 Asolfskalaheidi near Holt!, at an altitude of about 400 metres. 



This species is no doubt widely distributed over the whole of Ice- 

 land; it is, at any rate, rather common in E. and SW. Iceland, where 



29* 



