524 A. HESSELBO 



265. Rhynchostegium murale (Neck.) Br. eur. 

 Hypnnm murale Neck. 



S. Iceland: Drangshlid!; Hrutafell!. 



In the above localities it grew rather abundantly at the foot of 

 dry tuff rocks and on fallen blocks. The fruit was ripe in the latter 

 half of July, but some of the lids still persisted. 



266. Rhynchostegium rusciforme (Neck.) Br. eur. 



Hypnnm rusciforme Neck. 



N. Iceland: Near Eyjafjordur (O. D.)!. NW. Iceland: Isafjordur!. 

 W. Iceland: Dalsmynne in Nordredalur!; Lundurreykjadalur! ; Esja!; 

 Ellidara near Reykjavik!. S. Iceland: Tungufoss F.)!; Vik (H. J.)!; 

 Reykirdalur!, fr. ; frequent on Fljotshlid and near Eyjafjall!. 



Var. atlanticnm Brid. 



N. Iceland: Between Svinadalur and Dettifoss!; Husavik!. W. Iceland: 

 Esja!, in several places. S. Iceland: Reykirdalur!; Holt!; Vik (H. J.)!. 



The type is rather frequent in the Southern and Western parts of 

 Iceland, rarer in North Iceland, and has not been found in East Iceland. 

 It usually grows on wet rocks near waterfalls, or on stones in the rivers, 

 as a rule rather scantilj 7 , and mixed with Brachythecium riuulare, Hypnnm 

 ochraceum, etc. Only in Reykirdalur did it occur abundantly in the river 

 and on the rock-sides by the waterfall, also in fruit. 



Var. allanticiim is found in swiftly flowing rivers, where it often 

 covers the bottom and stones for long distances. 



267. Thamnium alopecurum (L.) Brid. 



W. Iceland : DalasVsla, Vogur H.J.)!; Jserngerdarstadr (Ssemundson)!. 

 S. Iceland: Reykirdalur!; Paradishellir (Stp.)!; common on Fljothlid and 

 below Eyjafjall!. 



On wet shady rock-faces and in caves. In S. Iceland it is common 

 in the tuff-clefts, especially on the inwardly sloping surfaces, and in the 

 numerous dark, damp caves, where it often covers the roof and sides 

 through which water is percolating. Only sterile specimens have been 

 found. 



268. Plagiothecium silvaticum (Huds.) Br. eur. 



N. Iceland: Grimsey (O. D.)!. S. Iceland: Thingvellir (Grl.;!); Al- 

 mannagja !. 



In Almannagja it was found scantily at the bottom of a lava-cleft. 

 Onry sterile specimens were found. 



2(>9. Plagiothecium Roeseanum (Hampe) Br. eur. 

 Syn. Plagiothecium silvaticum var. Roesei (Hampe) Lindb. 



Commonly distributed, but as a rule rather scantily, in soil-filled 

 rock -ere vices, in company with Mnium orthorrhynchiim, Plagiochila 



