EXPLANATION OF THE PLATES. 741 



membranous rudiment of the inner peristome and a portion of the annuius. of A. 

 obtnsifolius, Br. If Sck. 



OM ALT A. Plant, capsule with operculum, part of the peristome (one tooth, two cilia, one 



ciliola, and a portion of the annuius), and caly ptra, of 0. Wrightii, Sulliv. 

 HYPNUM. Plant, two capsules with opercula, part of the peristome (one tooth, on* c Ili- 

 um, and two ciliolae, with a portion of the annuius), and a calyptra, of H. salebrosum, 

 Hoffm. : after Schimper. 



Genera of Hepaticae. 



TAB. XX. 



BICCIA. Plant ; vertical section of the frond (showing two imbedded capsules and numer- 

 ous large air-cavities) ; spores enclosed in a mother-cell ; three free spores ; and caly p- 

 tra with its style, of R. natans, L. : after Bischoff. 



ANTHOCEROS. Plant ; portion of the two valves of the capsule and the columella, togeth- 



er with spores and elaters ; two spores and two elaters, of A. laevis, L. 



NOTOTHYLAS. Plants ; vertical section of the frond through the involucre, showing the 



capsule ; apex of the capsule protruding from the end of the involucre ; lower half of 



the capsule showing the columella ; upper half of capsule ; a gemma ; an antheridiuxn ; 



twelve free spores and two clusters of spores (4 in each), of N. valvata, Sulliv. 

 REBOULIA. Plant ; fertile receptacle viewed from above ; the same from below ; capsule 



dehiscing with remains of the calyptra at its base ; vertical section of the male disk, 



showing the imbedded antheridia ; an elater ; portion of the same ; and three spores, 



of R. hemfcphaerica, Raddi : after Bischoff. 

 SPttSROCARPUS. Plant ; a cluster of 5 involucres ; an involucre enclosing a capsule ; a 



capsule filled with spores ; and three spores, of S. Michelii. Bellardi: after Schweinitz. 



DUMORTIERA. Plants (portions of), male and female ; fertile receptacle, showing three 



involucres, each with. a capsule ; capsule partly covered by the calyptra ; vertical sec- 

 tion of the male disk, showing the imbedded antheridia ; an elater, portion of the 

 same ; and three spores, of D. hirsuta, Nets. 



PHAQIOCIIASMA. Plants ; triangular fertile receptacle with its three large involucres 

 seen from above ; same viewed sideways ; involucre with one side cut away, showing 

 the capsule and remains of the calyptra ; a capsule with remains of calyptra at its base 

 before dehiscence ; same after dehiscence ; an elater ; a piece of same more magnified ; 

 and two spores, of P. Wrightii, Suttiv. 



f EGATELLA. Plants (portions of), male and female ; a vertical section of the fertile recep- 

 tacle, showing two involucres, each with a capsule ; capsule with its caly ptra ruptured 

 at the apex ; vertical section of male disk showing the antheridia ; two elaters ; por- 

 tion of an elater ; and two spores of F. conica, Corda, : after Bischoff, partly. 



PREISSIA. Plants (portions of), male and female ; a vertical section of the fertile recep- 

 tacle ; perianth, calyptra, and capsule ; two elaters ; portion of an elater ; two spores ; 

 ind vertical section of part of the male disk, showing the imbedded antheridia, of P. 

 commutata, Nefs : after Bischoff, partly. 



MARCHANTIA Plants (portions of), male and female ; vertical section of the fertile recep- 

 tacle ; perianth, calyptra, and capsule ; an elater ; portion of the same ; five spores ; a 

 vertical section of a part of the male disk, showing the imbedded antheridia, of M. 

 ' polymorpha, L. : after Bischoff, partly. 



FIMBRIARIA. Plants ; a fertile receptacle ; vertical section of the same ; a capsule de- 

 hiscing ; two elaters ; and two spores, of F. tenella, Nees 



STEETSIA Plant ; portion of the frond, with involucre, perianth, and calyptra ; invo- 



lucre and perianth cut away so as to show the young calyptra ; capsule before dehis- 

 cence ; the same after dehiscence ; antheridium with its perigonial leaf ; an elater ; 

 and two sporules, of S Lyellii, Lehm. 



