8 4 



for years without producing anything resembling a fern 

 proper. Nay, more, it has even been found capable of 

 existing indefinitely in this shape and producing spores 

 without the intervention of fronds, quite possibly giving 

 thus a glimpse of fern origin pure and simple, viz. a 

 travelling, spore-bearing, lichen-like growth which, instead 

 of throwing up fruiting columns like many of the tribe, 

 evolved a chlorophyllic leafy frond instead, the better to 

 carry its spores and scatter them the farther, evolution of 

 the fittest doing the rest in time. 



In these green scales, which are usually the size o£ a 

 herring scale, but sometimes much larger, nearly an inch 

 across, there is no vascular or veinlike structure, the spore 

 produces first a shore row of cells, which then multiply by 

 fission until a heart-shape is assumed ; at the indentation 

 there is a thickened cushion, several cells thick, in which 

 a group of incipient seeds is imbedded, each one being 

 surmounted on the under surface of the scale by a teat- 

 like, hollow projection, termed an archegonium. These 

 form practically the female flowers. The under side of 

 the scale bears also a great number of whitish root-hairs, 

 which serve to attach it to the soil and nourish it, and 

 among these, scattered indiscriminately on the surface of 

 the scale, there are many small round-headed projections, 

 termed antheridia. These constitute the male flower, and 

 when ripe they burst, and the equivalent of pollen grains 

 is scattered forth in the shape of a crowd of very minute 

 ciliated organisms, i.e. tiny bodies, provided with movable 

 hairs, which enable them to swim actively about in the 

 dew-like moisture usually present beneath the scale or 

 prothailus. When liberated they swim towards the arche- 

 gonia, one or more of whose seed-cells become fertilized, 

 and shortly after this seed sends a root downwards and a 

 frond upwards, and a fern proper is thus launched into 

 ^existence. 



