THE BKYOPHYTA OF ICELAND 461 



hair point. In the birch coppices of NW. Iceland a form frequently 

 occurs on larger, scattered stones which, in habit, reminds one of 

 R. fasciculare. The tufts are flat towards the edge, dark-green; the hair 

 point is very short and often wanting. The forms from mountain 

 heights are often jet-black var. atrata} or on damp gravelly flats 

 yellowish green at the top, and grow in extensive, discontinuous mats. 

 a few cm. thick. The fruit, which is very common, ripens in the be- 

 ginning of June. 



88. Rhacomitrium heterostichum (Hechv.) Brid. 



E.Iceland: Hornafjordur!; Hof!; Geithellir!; Berufjordur!. X. Ice- 

 land: Akureyri!, at an altitude of 350 metres. NW. Iceland: Patreks- 

 fjordur!; Arngerdareyri!. Common in S. and \V. Iceland!. 



Common throughout E. Iceland, from Berufjordur, and southwards 

 through the whole of S. and \V. Iceland. 



In \V. Iceland it occurs abundantly at the head of Isafjordur, near 

 Arngerdareyri, but has not been collected about the fjord further out- 

 wards towards its entrance; it was also common by Patreksfjordur. It 

 appears to be more rare in N. Iceland. 



The plant grows most frequently on dry rocks, and more rarely 

 on those that are damp; it occurs in masses, for instance, in the lava 

 districts of SW. Iceland. It is most common in the low land, but is, 

 however, also met with at about 600 metres above sea-level. Fruit 

 is rather common. 



89. Rhacomitrium microcarpum Brid. 

 Grimmia ramnlosct Lindb. 



X. Iceland: Hof by Eyjafjordur (O. D.)!, sterile. 



Recorded by Gronlund from Reykjavik and Husafell, but the 

 specimens in the Botanical Museum in Copenhagen must be referred to 

 R. canesccns. 



90. Rhacomitrium canescens (Weis) Brid. 

 Verv common. 



> 



Next to R. hypnoides the most widely distributed species, and met 

 with as frequently on mountain heights as in the low land, and in 

 numerous forms. It grows both on rocks and on earth, especially 

 \vhere it is somewhat damp. In the "Grimmia heath" it often covers 

 the more low-lying tracts with its light yellowish-green to greyish-green 

 mats, while R. hypnoides grows in the more dry parts, but both species 

 often occur mixed. It is also the most abundant constituent of the vege- 

 tation on damp sandy or gravelly soil by streams, in grass-fields with 

 a poor soil, etc. Forms with the hair point entirely or almost wanting 

 (f. epilosa) are frequent in wet localities. 



Fruit is only rarely and scantily met with. Near Hof in E. Ice- 

 land plants were found in the middle of June with old capsules, and 

 near Sugandafjordur about July 1st with yet green capsules. 



