CHAPTER X. CRYPTOGAMS 

 I. THEIR PLACE IN NATURE 



331. Order of development. All the forms that have 

 hitherto claimed our attention belong to the great division 

 of Spermatophytes, or seed-bearing plants, designated also as 

 Phanerogams, or flowering plants. They comprise the higher 

 forms of vegetable life, and because they are more conspicu- 

 ous and better known than the other groups, they have been 

 taken up first, since it is more convenient, for ordinary pur- 

 poses, to work our -way backward from the familiar to the less 

 known, rather than in the reverse order. 



But it must be understood that this is not the order of 

 nature. The geological record shows that the simplest 

 forms of life were the first to appear, and from these all the 

 higher forms were gradually evolved. There is no sharp 

 line of division between any of the orders and groups of 

 plants, but the line of development can be traced through a 

 succession of almost imperceptible changes from the lowest 

 forms to the highest, and it is only by a study of the former 

 that botanists have come to understand the true nature and 

 structure of the latter. 



332. Basis of distinction. - - Cryptogams, or seedless 

 plants as a whole, are distinguished from the phanerogams 

 by their simpler structure and by their mode of propagation, 

 which in the former is by means of spores, while in the 

 phanerogams it is by seeds. A spore is a simple organic 

 body, consisting usually of a single cell which separates from 

 the parent plant at maturity and gives rise to a new individual. 

 A seed is a complicated, many-celled structure, containing 

 within itself the rudimentary structure of a new plant already 

 organized. 



