POLYTR1CHUM THE SPOROGONIUM 351 



vaginula, which belongs to the oophyte generation. 

 With this close physiological connection of the sporo- 

 phyte and oophyte in the Moss, compare the connection 

 by means of the foot in Ferns. 



Similar sections may be prepared, with similar results, from 

 plants of Funaria, but there will be greater difficulty in this case, 

 owing to the smaller size of this Moss. 



XII. Passing now to the apex of the sporogonium 

 of Polytrichum, remove the calyptra : mount it in 

 water or weak glycerine, and examine under a low 

 power. It consists of dry, often branched, hypha-like 

 filaments, loosely matted together : the neck of the 

 archegonium may often be recognized at its extreme 

 apex. 



The calyptra of Funaria may be treated in a similar 

 way : here the brown neck of the archegonium is clearly 

 seen, while the body of the calyptra consists of a con- 

 tinuous tissue, a single layer of cells in thickness. 



XIII. It will be found convenient to take first the 

 capsule of one of the simpler Mosses, e.g. Funaria. 

 and subsequently to proceed to a more complicated 

 example, e.g. Polytrichum. 



After noting the oval form, and the obliquely placed 

 operculum, embed capsules of Funaria, which have 

 been hardened in alcohol, in paraffin : cut median 

 longitudinal sections : mount in glycerine or in glycerine 

 jelly, and examine first with a low power. 



N.B. It will be well to select young capsules of such age that 

 the peristome (seen through the operculum) shall show a pale 

 yellow tinge : later it assumes a dark yellow or orange colour, and 



