454 



A. HESSELBO 



S. Iceland: Thorlakshver, on warm claj^ey ground. 



Allhough this form differs somewhat from B. fallax in habit, in the 

 smootli leaves with rounded apex, and in llie divergent form of tlie 

 perichætial leaves, yet there is hardly any doubt tliat it must be re- 

 ferred to this species. Setting apart the absence of papillæ the leaf- 

 tissue is quite typical, and tlie form and the plication of the lower 

 leaves are exactly as in B. fallax. It should be remembered that the 

 occurrence on a warm substratum produces very divergent forms also 

 in other mosses, e. g. Philonotis. Catharinea and Oligotrichiim. Near 

 Reykir, B. fallax was coUected both on stones by the river, in sand- 



Fig. 1. Biirhula fallax Hechv. a, Leaves of the plant from Rej-kir (X 20) 

 var. hvvifoUa : c, perichætial leaves of same. 



Z>, Leaves of 



fdled tiifts about 2 cm. high, in a somewhat typical form, and on a warm, 

 damp substratum. Piants from the latter locality form a transilional 

 stage to var. lævifolia. It grew in somewhat loose tufts, 3—4 cm. high, 

 which in colour and appearance agreed with var. lævifolia. The lower- 

 most leaves are pointed, the uppermost rounded: the perichætial leaves 

 are lanceolate, rounded, with rather faint nerve. The leaf-cells are di- 

 stinctly papillose, sometiiues as highly as in the typical form, some- 

 times much more faintly. 



64. Barbula cylindrica (Tayl) Schimp. 



N. Iceland: Hof near Eyjafjordur (O. D.)!. S. Iceland: Vestmannaey ! ; 

 Vtri Skogur (H. J.)!; Fljotshlid!; Holt!; Drangshlid!; Hornafjordur!. 

 W. Iceland: Esja near Kollatjordur !. 



This species occurred commonly, and often abundantly, on tuff-rocks 

 in S. Iceland and on Vestmannaey. There it also grew^ abundantly on 

 sandy soil and on lava blocks near the sea. In the other localities it 

 was found but scantily. Fruit was collected only near Holt, where, at 

 the end of July, both old and yet green capsules were collected from 

 the same tuft. 



