270 



HANDBOOK OF BRITISH HEPATIC^. 



lucre at the apex of the peduncle, quaternate, cru- 

 ciate, spreading horizontally (fig. 

 188), apex vertically bilabiate, 

 monocarpus. Perianth none. 

 Calyptra included, crowned with a 

 style, splitting above, pedicels the 

 length of the involucre. Capsule 

 exerted, thin, four to eight valved, 

 valves spreading, somewhat 

 twisted. Elaters bispiral, de- 

 ciduous. Pistillidia four to six, in 

 discoid receptacle, sessile, super- 

 ficial, girt by paraphyses. Male 

 188. receptacle oblong, at the sinus of 



the frond, sessile on the upper 



surface, girt by an elevated margin. — {Plate 'J.fig. 



93) 



Genus 43. PREISSIA, Nees. 



Female receptacle pedunculate, hemispheri- 

 cal, four-lobed, rays of the lobes shorter, rib- 

 like. Perianth obconically campanulate, angu- 

 lar, unequally four or five parted. Calyptra 

 persistent. Capsule shortly pedicellate, cut into 

 four or eight irregular valves. Elaters bispira'. 

 Male receptacle pedunculate, peltate, repand, 

 lobate. Margin thin. Fronds sparsely forked, 

 bearing the peduncle from a sinus of the ter- 

 minal lobe. 



Preissia commutata, N. 

 Male receptacle peltate, pedunculate; fe- 



