The manner in which the spores originate in the sporangium calls for comment. In the case of the Male Fern these arise owing to the repeated division of a single cell. At a certain stage in the process there are produced what are known as mother cells. Ultimately these divide twice, and the resulting cells represent the spores. When ripe, the spores become kidney-shaped and the wall of the cell takes on a rich brown colour. In the different kinds of Ferns, the form of the spore and the sculpturing of its walls vary a great deal. Thus the spores may be globular, oval, or angular in shape; whilst the exterior may be quite plain, or, perhaps, most beautifully marked. The number of spores produced in the sporangium of a Male Fern is usually some forty-eight to sixty-four, although in other species there might be less than the lower figure or more than the higher. To the naked eye the spores appear to be so much dust, and as they are comparatively light they float away on the breezes, and often enough travel for a considerable distance before coming to rest. As a rule the bursting of the sporangia takes place during dry weather. There is a real advantage in this, for when the spores are damp they hang together in masses and in such a state a wide dispersal would be out of the question.
The best thing that can happen to the spore is that it should settle upon some moist soil. Here it may be mentioned a most instructive experiment is the sowing of a few fern spores. This may be carried out in ordinary garden soil, although it is wise to sterilize it before use. All soil contains the germs of such organisms as mould which, in cultivation at any rate, is especially destructive to developing spores. The plan is to bake the mould in an oven until it is so hot that one cannot bear to touch it. We shall get any number of spores from the fertile leaf of a Male Fern by just tapping the frond whilst holding it over the surface of the soil. Do not scatter the spores too thickly, or it will be difficult to examine the stages of development, and remember also that the soil should be moist at the start. The results of this spore culture are always more satisfactory if the soil is covered with a bell-glass--an ordinary tumbler would do if nothing better is available. Water must be given as necessary, though do not swamp the soil; the best plan is to let the liquid in a few drops at a time.