EXPLANATIOX OF PLATE XXII. 



RICCIA. — riant of K. natans; section of tliallus, sliowiiif;- two imbedded 

 capsules and numerous air cavities; spores enclosed in a mother-cell; 

 three free spores; and calyjjtra with style. 



ANTHOCEROS. — Plant of A. kevis; portion of the columella and valves of 

 the capsule, with spores and elaters ; two spores and two elaters. 



NOTOTHYLAS. — Plants of N. orbicularis; section of the thallus through 

 the iiivolucre ; apex of protruding capsule ; lower lialf of capsule showing 

 the columella ; upper half of capsule ; a gemma; an antlieridiuni ; twelve 

 free spores, and two clusters of spores (4 in each). 



ASTERp]LLA. — Phmt of A. hemispha^rica; 9 receptacle viewed from 

 above; the same from l)elow ; capsule dehiscing, Avitli remains of calyp- 

 tra at base; section of J disk ; an elater, a portion of same, and spores. 



SPILEROCARPUS. — Plant of S. terrestris; cluster of five involucres; in- 

 volucre enclosing a capsule; capsule filled witli spores; and three sports. 



DUMOR'ITERA. — Portions of J and 9 jdants of 1). liirsuta; 9 receptacle 

 sliowing tliree involucres, two witli capsuh's; ca] sule with calyptra ; sec- 

 tion of J disk; elater and ])ortion of same; sjtores. 



ArrONIA. — Plaiit of A. Wriglitii ; upper view of 9 receptacle with throe 

 involucres; si.le view of same; involucre partly cut away showing cap- 

 sule and remains of calyptra; a capsule closed, and dehiscent; an elater, 

 a piece of same, and spores. 



CONOCEPHALL'8. — Parts of $ and 9 ])lants of C. conicus; secti(m of 9 

 receptacle, showing two involucres and cajjsules; capsule with ruptured 

 calyptra; section of J* disk; elaters, a ])ortion of one, and spores. 



PREISSIA. — Parts of $ and 9 jdants of P. commutata; section of 9 re- 

 ceptacle ; perianth opened showing calyptra and capsule ; section of part 

 of $ disk ; elaters, a part of one, and spores. 



MARCHANTIA.-— Parts of $ and 9 plants of M. polymorpha; section of 

 receptacle ; perianth, calyptra, and capsule ; section of part of $ disk ; 

 an elater, pai-t of same, and sjiores. 



PIMBRIARIA. — Plant of F. tenella; 9 receptacle, and section of same; 



capsule dehiscing ; elaters aud spores. 

 PALLAVICINIA. — Plant of P. Lyellii; part of thallus with involucre, iieri- 

 anth, and calyptra; perianth cut away showing young calyptra ; capsule 

 closed, and dehiscent ; antheridium enclosed in a leaf ; elater and spores. 



