C 9 ) 



F 



FERNS, AND THEIR ALLIES. 



ERNS are regarded as the highest in the scale 

 of cryptogamic plants, and have always been 

 great favourites. Perhaps none of the lower orders 

 have been so much sought after, or so well investi- 

 gated, so that their number may be estimated with 

 something of certainty. In 1847 the total number 

 of ferns, with their allies, was fixed by Lindley at 

 2264; but since that period the " Species Filicum," and 

 other works, have augmented the number consider- 

 ably, so that it cannot now fall much below 4000, 

 and this, with 565 fern allies in 1887, would at least 

 raise the total of ferns and fern allies to 4600 species. 

 This estimate is based upon Hooker's and Baker's 

 " Species Filicum," with the " Supplement," and 

 Baker's " Fern Allies." 



Although the ferns may have somewhat the appear- 

 ance of flowering plants, it is by no means difficult 

 for any ordinary person to distinguish them. In 

 almost all cases it is sufficient to look at the under 

 surface of the leaf or frond, when it will be observed 

 that this under surface is not naked, as in an ordinary 

 leaf, but furnished at regular distances with roundish 

 or elongated brown elevated spots, or tufts, which a 

 common pocket lens will demonstrate to be composed 



