THE BRYOPHYTA OF ICELAND 449 



The entire height of the plant was about G mm. The seta was 

 about 5 mm. high. The capsules were, without the lid, about 0.5 mm. long. 



47. Ditrichum homomallum (Hedw.) Hampe. 



Fl. Dan. tab. 2688, ex Islandia leg. Morch. E. Iceland: Vestdalur 

 near Seydisfjordur!, sterile. N. Iceland: Hof near Eyjafjordur O. I).)!, 

 sterile. W. Iceland : Reykjavik (Grl.;!), fr. ; hot spring near Grafarbakki 

 (F.)!, sterile; Hafnarfjordur, at the bottom of a lava cave!, sterile. S. Ice- 

 land: Geysir! $. 



Around Reykjavik it was rather common along the side of ditches. 

 There the fruit was ripe on August 7th. Near Geysir it occurred in 

 extensive mats, about 1 2 cm. deep, on warm clayey flats with a tem- 

 perature of 3540. 



48. Ditrichum flexicaule (Schleich.) Hampe. 



One of the most commonly occurring mosses; it is met with on 

 almost every substratum and at all altitudes. It grows both on damp 

 or soil-covered rocks and in bogs, where it especially occurs woven 

 into the tufts found there, and on damp or on more dry gravelly soil, 

 in lava caves, in grass fields, in heaths, etc. 



This species varies considerably, especially as regards the length 

 and direction of the leaves. Short-leaved forms (/. brevifolia) are fre- 

 quent on more dry ground, where they form dense tufts with stiffly 

 erect or slightly secund leaves. On damp ground and especially in 

 sheltered localities, for instance among stones, or in clefts, the leaves 

 become longer, often strongly secund, and the tufts higher and looser. 

 Fruit it very rare. Near Seydisfjordur, in the beginning of July, the 

 setae had not developed to their full length and the capsules were 

 barely formed. 



r 



49. Saelania caesia (Vill.) Lindb. 

 Ditrichum glaucescens (Hedw.) Hampe. 



E. Iceland: Breiddalur!; Hallormstadr!. N. Iceland: Vidimyri (Grl.)!; 

 several places near Eyjafjordur (O. D.;!). W. Iceland: Husafell (Grl.)!; 

 Kalmanstunga (Grl.)!; Gilsbakki!; Hafnarfjordur!; Esja!. S. Iceland: Skal- 

 holt!; common near Thingvellir!. 



This species is rather common, especially in \Y. and S\V. Iceland, 

 in soil-filled rock and lava clefts, as a rule associated with Miiium 

 orthorrhynchum , Plagiothecium Roeseamim, P. piilchellnm , Pohlia cnula, 

 Distichiam montamim, etc. 



In the wood by Hallormstadr it was growing on the ground in 

 company with Bartramia ityphylla, Pohlia cruda , Distichinm inclinatnm 

 and Ditrichum flexicaule. The fruit, which is almost always present, 

 ripens in the middle or at the end of June. The plant has not been 

 observed at a higher altitude than about 200300 metres. 



