424 A. HESSELBO 



hraun (Gri.; Stp.;!); Krisuvik (Stp.)!; Holt!; Reykirdalur!, at an altitude 

 of about 260 metres. 



Diplophijllum albicans is a plant characteristic of the lava-fields of 

 West and South Iceland and occurs there in great abundance on ver- 

 tical rock-sides in clefts and caves, while it appears to be entirely ab- 

 scnt from the lava-fields of North Iceland. Outside the lava-fields it 

 has been gathered only extremely sparingly among stones on heaps of 

 debris at foot of cliffs (Urd). In Reykirdalur it grew scantily on a warm 

 substratum among large blocks of basalt. Only sterile specimens have 

 been found. 



77. Diplophyllum obtusifolium (Hook.) Dum. 



"In Islandiae montibus leg. Morch" and figured in Flora Danica, 

 tab. 1831, tig. 2. No specimens of it are to be found in the herbarium 

 of the Botanical Museum. In the district of Seydisfjordur!, on a damp 

 rock-face by the river it occurred in a small quantity in a tuft of Di- 

 cramim molle and Lophozia Kunzeana. In N. Iceland: Asbyrgi!, it was 

 found on the ground among fallen blocks of lava. Only sterile specimens 

 have been found. 



78. Scapania subalpina N. ab Es. 



Common on damp ground along streams, on damp rocks, in clefts 

 and on damp slopes of the low land. It does not appear to ascend 

 much higher than about 300 melres. 



(^ piants are very common; calyces and fruit occur occasionally. 



The plant varies in having deeply toothed to almost entire leaves. 

 It is usually green or yellowish-green in colour, but sometimes reddish 

 or brownish to almost blackish-brown in more exposed localities. 



79. Scapania remota Kaalaas. 



N. Iceland: Akureyri!. 



The plant, which agreed exactly wilh the description and figure 

 in Karl Miiller's Monographie der Lebermoosgattung Scapania, grew 

 in the above locality, in a bog 400 metres above sea-level, intermixed 

 in tufts of Oncophoriis virens. 



80. Scapania irrigua (Nees) Dum. 



Very common on damp ground, in bogs, along streams and on 

 damp rocks. 



This species is most widely distributed in the lowlands up to 

 about 300 metres above sea level, but may also frequently be tuet with 

 at high attitudes in the Alpine regions. In wet localities, espccially 

 in bogs, where it occurs everywhere woven into the tufts of other 

 Bryophyta, it is usually yellowish green in colour. The leaves are en- 

 tire or fewly toothed towards the apex with thin-walled or slightly 

 collenchymatous cells. But occasionally vigorous, brownish-green forms 



