32 FOOTNOTES FROM 



matter. As to the motion, how are we to tell that it 

 is not a hygrometrical action, like that of the teeth which 

 fringe the mouth of the capsule ?" Be their nature, 

 however, what it may, they are extremely curious ob- 

 jects, and well worthy of the most careful examination. 

 In the same receptacle, among the upper leaves of the 

 moss, may be seen antheridia in every stage of develop- 

 ment, those in the centre appearing to ripen first, even 

 while some of those at the outer edge are of small size 

 and quite green. There is thus a constant succession of 

 phytozoa produced; a provision which tends to insure 

 their application to the pistilidia at the proper time. 

 Several species of mosses are furnished with gemmae or 

 pseudopodia, which consist of -powdery or granulated 

 heads terminating an elongated and almost leafless por- 

 tion of the stem. These organs are usually developed 

 only in unfavourable circumstances, being formed at the 

 expense of the fruit which is then abortive. They ap- 

 pear to be simply a mass of naked seed, without the 

 ordinary protection and mechanism of an enveloping 

 seed-vessel, and as such, afford a remarkable illustration 

 of the simplicity of the means by which nature, when 

 placed at a disadvantage, effects her vital purposes. It 

 is worthy of remark, that there are several mosses which 

 possess the power of maintaining and spreading them- 

 selves without the aid of any of these organs of fructifi- 

 cation. There is one remarkable species, the male plant 

 of which exists only in Europe, so far as can be ascer- 

 tained, and the female only in America, and yet they 

 propagate themselves with as much facility as though 

 they grew side by side in the same crevice of rock. 



