TYPES OF CRYPTOGAMS; BRYOPHYTES 285 



of the capsules, examine with a magnifying glass, and sketch it. 

 Note the character of the material of which its outer layer is 

 composed. 



Sketch the uncovered capsule as seen through the magnifying 

 glass, noting the little knob at its base and the circular lid. 



Pry off this lid, remove some of the mass of spores from the 

 interior of the capsule, observe their color as seen in bulk through 

 the magnifying glass, then mount in water, examine with the high- 

 est obtainable power of the microscope, and sketch them. These 

 spores, if sown on moist earth, will each develop into a slender, 

 branched organism, consisting, like pond-scum, of single rows of 

 cells (Fig. 207) called the protonema. 



347. Other Reproductive Apparatus. The student cannot, with- 

 out spending a good deal of time and making himself expert in the 

 examination of mosses, trace out for himself the whole story of the 

 reproduction of any moss. It is sufficient here to give an outline of 

 the process. The protonema develops buds, one of which is shown 

 in Fig. 207, and the bud grows into an ordinary moss plant. This 

 plant, in the case of the pigeon-wheat moss, bears organs of a some- 

 what flower-like nature, which contain either antheridia (Fig. 208), 

 organs which produce fertilizing cells called antherozoids, or arche- 

 gonia (Fig. 209), organs which produce egg-cells, but in this moss 

 antheridia and archegonia are not produced in the same "moss- 

 flower." The plants therefore correspond to dioecious ones among 

 flowering plants. 



After the fertilization of the egg-cell, by the penetration of 

 antherozoids to the bottom of the flask-shaped archegonium, the 

 development of the egg-cell into sporophyte begins ; the latter rises 

 as a slender stalk, while the upper part of the archegonium is 

 carried with it and persists for a time as the hood or calyptra. 



