THE BRYOPHYTES 429 
carries it upward as the covering of the capsule, or calypira. 
The calyptra is thrown off before the spores are matured within 
Fig. 322. Fic. 323. 
Fic. 322.—Funaria hygrometrica. A, Young sporophyte (c) attached to gameto- 
phyte (g). B, Adult sporophyte with seta (s) and capsule (f); gametophyte (g), 
part of which forms the calyptra (0). C, Vertical section of capsule (X 80). 
Operculum (d); Peristome (p); Annulus (2); Air-space with trabeculz or filaments 
(t); Sporogenous layer (s). (From Small, after Prantl.) 
Fic. 323.—Surface view of peristome of Funaria, after removal of operculum. 
pf, peristome tooth. (After Small.) 
the capsule. The upper part of the capsule becomes converted 
into a lid or operculum at the margin of which an annulus or ring of 
thick-walled cells forms. Attached to the annulus by their bases 
Male Votant Sperm 
. Nantheria ee Fertil ized—Sporophyte —Spore 
Female plant—Archegonium —Egg egg 
Fic. 324.—Diagram of the life history of a moss. (After Atwood.) 
Spore Protonema ~<e 
are a number of long triangular teeth called collectively the 
peristome. The cells of the annulus are hygroscopic and expand 
