196 Atkinson . — A Monograph of the 
Wartmann 1 a little later described its development, 
Sirodot 2 fully described the Chimtransia- form (‘thalle’) , 
of several species, noted some which had been described and 
catalogued as species of Chantransia , and noted also the 
differences between the real Chantransiae and the Chan - 
transia- form of the Lemaneaceae. 
This phenomenon of a polymorphic protonema in the oophyte 
of Lemanea obtains in some other algae as well as in some of 
the Muscineae. In the oophyte of Batrachospermum Sirodot 4 
has shown, and the author has demonstrated in the case of 
one of the American species 5 , that in one series the carpo- 
spore develops a prostrate cellular permanent form of the 
protonema. This gives rise to the Ckantransia-iorm which 
is a real Chantransia- plant and not only bears gonidia, but 
gives rise as well to the sexual Batrachospermum- plant. The 
protonema is increased not only by multiplication of the cel- 
lular prostrate form, and from rhizoids at the base of the 
Chantransia-iorm, but in addition is multiplied directly from 
the gonidia of the Chantransia-^ orm. 
In the Muscineae polymorphism of the protonema is com- 
mon in such genera as Mnium , Bryum % Barbula , etc., where a 
secondary protonema (erect form) may be produced from the 
rhizoids by turning them up and keeping them in a moist 
condition for a few days. The rhizoids are morphologically 
comparable to the prostrate form of the protonema of 
Lemanea , not so much because they are prostrate, but 
because in many species 6 (of Phascum , Funaria , Pottia) they 
are the permanent form, and render the plants ‘virtually 
perennial ’ by the aid of their rhizoids : the plants disappear 
entirely from the surface of the ground after they have 
1 Loc. cit. 
2 Ann. d. Sci. Nat., etc., 1872, Comptes Rend., 1873, and Les Batracho- 
spermes, 1884, loc. cit. 3 Loc. cit. 
4 Sirodot, Les Batrachospermes, Paris, 1884; Observations sur le Devel. d. Alg. 
d’eau douce, comp, le genre Batrachospermum, Bull. d. 1 . Soc. bot. d. France, xxii. 
1875. 
5 Manuscript notes. 
6 Goebel, Outlines of Class, and Special Morph, of Plants. 
