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The reproduction of ferns from spores is a study of much interest, and one worthy of mare general attention. The modus operandi is fraught with difficulties. The minute size of the infant ferns in their first growth is in itself dangerous, as any neglect will at once destroy the whole crop. The spores germinate as mere green points, imperceptible at first to the unassisted eye, and only rendered visible by the look of greenness from a number springing into life together. Spores of ferns differ from seeds of plants, inasmuch as they have n special organs; consisting merely of a homogeneous cellular mass. In seeds the young roots and the young shoots are present in the embryo, being developed from determinate points; whilst spores, on the contrary, consist merely of single vegetable cells, growing indifferently from any part of the surface.

These points of life, (germinant fronds,) as they continue to grow have a strong resemblance to Liverwort, (hence the term Marchantia-like.) They gradually increase in size, and, they de net become impregnated, will occasionally exceed half an inch in diameter.

The impregnation of the germinal frond does not seem to be capable of being accomplished without the action of strong light; indeed, grown in a somewhat dark corner the growth seems to be arrested before arriving at that particular stage of life. The following experiment will illustrate what is meant:—Three years ago a large Wardian case was prepared, and the surface of the soil scattered over with spores from a number of varieties of Scolopendrium vulgare, Lustrea filix-mas, Athyrium filix-fœmium, Polystichum angulare, and of Lastrea dilatata; each species being in a separate partition, This case was placed in a somewhat dark corner, under a plant stage. When the spores had been sewn about six months the whole surface soil was covered over (and had been for several weeks previously) with the vivid green of the young ferns. At this time a second case was prepared, not for spore sowing, but for transplanting, in patches, the germinal fronds from the first case. Small portions of this green mass were lifted on the point of a knife and planted in thick lines. The second case was then placed in a light part of a greenhouse, having a north aspect. Under these circumstances the transplanted patches very soon grew rapidly, (whilst those in the case from which they were taken had made little or no progress.) and in six months the second case was filled with a mass of fronds, yet no fronds appeared in the original case. A third ease was then prepared, and for the second time small portions were removed from the first case into the new one, and this also was placed in a well-lighted situation, having a north aspect. After being in this third case less than six months a large number of fronds appeared, whilst still no fronds appeared in the original case. A fourth case is now about to be planted from the same original stock, which, although still looking green and healthy, has no fronds developed, and, indeed, the germinal fronds it contains are still little more than mere points. Thus, for three years the growing spores in a darkened corner have remained all but dormant, whilst those transplanted from it have, in a situation of stronger light, a forest of fronds, varying between one inch and six inches in length, according as they have been selected from the second of third cases. This is mentioned as a very curious fact.