516 A. HESSELBO 



rather scantily in Botnsdalur and in a few localities in Esja. and in S. 

 Iceland it has not yet been observed. 



It grows on a damp substratum, both on rocks and on soil up to 

 about 400 metres above sea-level. Thus in N. and E. Iceland it is one 

 of the most frequent species on wet gravelly ground. Only sterile 

 specimens have been found. 



238. Cylindrothecium concinnum (de Not.) Schimp. 



Entodon orthocarpus Lindb. 

 X. Iceland: Vididalr (Grl.)!. S. Iceland: Mri Skogar (H.J.)!. 



239. Climacium dendroides (L., Dill.) W. et M. 



Very common over the whole of Iceland. 



Grows on damp substrata of every kind, especially in bogs, scat- 

 tered among other mosses, but also on soil covered rocks and damp 

 gravelly ground; frequent also on more dry ground among grass. It 

 hardly ascends higher than about 300 metres. Fruit was found only 

 in E. Iceland below Fjardarheidi. 



240. Isothecium myurum (Pollich) Brid. 



SW. Iceland: Hafnarfjordur!. S.Iceland: Holt!; Hrutafell!; Drangs- 

 hlid!; Vestmannaey !. 



This species was only found in the south-western part of the 

 country, where it was, however, rather frequent; and in the district 

 south of E\ T jafjall it was abundant in several localities, especially near 

 Drangshlid, where it grew abundantly at the foot of perpendicular tuff- 

 rocks facing south. Only sterile specimens have been found. 



241. Isothecium tenuinerve Kindb. 

 Isothecium myurum var. piliferum C. Jens. 



E Iceland: Papey (St.)!. NW. Iceland: Duijandi!; Arngerdareyri ! . 

 W.Iceland: Stykkisholmur ! ; Budahraun (H.J.)!: the hot springs near 

 Reykjavik (Grl.;!); Yidey!; Esja!; Hafnarfjordur!; the lava-fields around 

 Reykjavik!. S.Iceland: Holt!; Thingvellir!; Kihlhraun!; Krisuvik Stp.)!. 



Common in the southern and south-western parts of the country 

 in lava caves and clefts, probably also common in W. Iceland. In NW. 

 Iceland rarer; and only found in one locality in SE. Iceland Occurs 

 in greatest abundance in lava clefts, for instance abundantly near Thing- 

 vellir. Only sterile specimens have been found. 



242. Homalothecium sericeum (L.) Br. eur. 



Very common over the whole of Iceland. 



Grows on dry, more rarely on damp rocks, and often abundantly 



