—47— 

 A^.?£-^ (of the capsule), the lowest part just above the point 

 where it joins the seta. See also collum. 



Nodose, covered with knots or prominences. 

 Nodulose, covered with very small knots or prominences. 

 (The cilia in Fig. 43.) 



Ochrea, a thin sheath around the base of the seta, terminating 

 the vaginula. 



Operculum, the lid which closes the capsule and, falling, per- 

 mits the spores to escape. (Figs. 32, 37, .jo.) 



Pachvderinous, thick skinned; applied to the walls of cap- 

 sules or to cells when firm and resisting. 



Papillose (of the seta), rough with small 

 rounded or acute protuberances. (Fig. 42 ) 

 Pedicel, =sela, which see. 

 Pendulous, somewhat hanging or drooping; 

 more so than in cernous. (Fig. 40.) 



Peristome, the fringe surrounding the mouth 

 of the capsule upon removing the lid. This 

 fringe may consist of a single row of processes, 

 known as teeth, as in Fig. 31, or of 

 a double row as in Fig. 43. In 

 the latter case the entire fringe is 

 still the peristome, but the term is 

 also applied in a particular sense 

 to the outer row; the outer row is 

 often spoken of as the exostome 

 {b), and the inner as the endostome 

 {c). The inner row consists of as 

 many projections as the outer, but 

 alternating with them ; these are 

 known as processes or segments 

 (( ). Between the segments there 

 are often one or more slender hair- 

 like processes known as cilia. 

 (Fig. 43, d ; fig. 36, c.) 



Moss peristomes, viewed with a 

 compound microscope, are among 

 the most beautiful of natural ob- 

 jects. They are not composed of 

 cells (except in the Polytrichaceic and a few other small families), 

 but of thickened cell walls. The cross markings on the teeth, 

 segments, and cilia are the lines of junction of the transverse cell 

 walls with the longitudinal cell walls forming the peristome. The 



