524 A. HESSELBO 



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



Hypmim miirale Neck. 



S. Iceland: Drangshlid!; Hrutafell!. 



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

 dry tufT rocks and on fallen blocks. The fruit was lipe in the latter 

 halt" of Jiily, but sonie of the lids still persisted. 



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



Hypmim rusciforme Neck. 



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

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

 Ellidarå near Reykjavik!. S. Iceland: Tungufoss F.)!; Vik [H. J.)!; 

 ReykirdalurI, fr.; frequent on Fljotshlid and near Eyjafjalll. 



Var. affaHfictrni Brid. 



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

 Esja!, in several piaces. S. Iceland: ReykirdalurI; 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 scantil}^ and mixed with Brachyiheciiim riviilare, Hypmim 

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

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



Var. atlanticiim 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.)!; Jærngerdarstadr (Sæmundson)!. 

 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- 

 mannagjå!. 



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

 Onlj' sterile specimens were found. , 



269. Plagiothecium Roeseanum (Hampe) Br. eur. 



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



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

 rock-crevices, in conipany with Mnium orthorrhynchiim, Plagiochila 



