HANDBOOK OF BRITISH HEPATIC^. 287 



SUB-GENUS 2. RICCIELLA; Braun. 



Fruit globose, exserted, adnate to the 

 lower surface of the frond. Braun. Bot. Zeit. 

 1821, p. 756. 



Rieciella fluitans, Br. 



Frond dichotomous, J to 2 inches in length, 

 yellowish green, repeatedly forked, laciniae 

 linear, narrow, obtusely emarginate, and forked 

 at the apex, sometimes thickened, usually 

 membranaceous, channelled, margin and be- 

 neath of the same colour. 



Riccia fluitans, Linn. Sp. 1606 ; Eng. Bot. 

 t. 251; Lindenb. Mon. t. xxix., xxv. ; 

 Hook. Muse. Britt. 213; Eng. Fl. V., i., p. 

 98; Cooke Hep. f. 198. Rieciella fluitans, 

 Braun. Flora, 1821, p. 754; Lindenb. Syn. 

 p. 115; Carr. and Pears. Exs. 140. Lichen- 

 astrum aquaticum, Dill. Muse. 514, t. 74, 



f. 47 . 



Floating on stagnant water, 

 var. ]3 canaliculata, narrower, margin ele- 

 vated, sulcate. 



The fronds float on stagnant water, amongst 

 duckweed, or occasionally root in the 

 soil at the margin, when they are of 

 a smaller size ; of a yellowish-green 

 colour, from I to 2 inches in length, 

 the segments linear, but a little en- 

 larged towards the apex, which is 



