168 CBYPTOGAilS 



the cone terminating tlie fei'tile shoot. Dissect the cone under the 

 lens. Note the peculiarly moilihed leaves: how many saclike folds 

 has each? Is the number constant? "What is the natnre of tlle^e 

 "folds " as determined by the contents ? Draw a diagiammatic longi- 

 tudinal section of one of the cone leaves, much enlarged. 



403 (Compound). With the compound microscope examine tJie 

 contents of the sacs. Draw. Allow some of the spores to dry on a slide, 

 and then, while viewing them through tlie microscope with a low- 

 power, breathe out gently so that the moisture from tlie breath will 

 strike the spores. Describe the action seen, illustrating by diagrams. 



XVI. CRYPTOGAMS 



404. The plant.s to be described in tlie present chapter 

 are a few chosen from a very great number of forms, 

 making up a series whicli dilTers in many important re- 

 spects from tlie group of Phanerogams. C'i'ypti:)gam.s on 

 the whole are smaller than Phanerogams. It is true that 

 the Ferns (cryptogamous plants) are a conspicuous element 

 of land vegetation almost everywliere, and in the warmer 

 region.s attain to the stature of trees ; and that Seaweeds, 

 some of them of great size, hold exclusive possession of 

 the littoral rocks ami the borders of the ocean lied. But 

 the great majority of cryptogamic forms are too small to 

 attract attention, and many are even too miiutte to be seen 

 by the naked eye. Although many of the Cryptogams, 

 both great and small, have a ver}' varied life histoiy and a 

 structure that is by no means very easy to understand, yet 

 as a group tlie Cryptogams are structurally simpler than 

 the Phanerogams. 



405. Viewing all cryptogamic plants together, we find 

 that they fall into a kind of series, which, if followed in 

 one direction, leads toward the general type of organization 

 fmmd in Flowering Plants ; or, in the other direction, leads 

 towaril the simplest microscopic forms. The series is, 

 however, a very imperfect one, broken b\" many gaps. 

 Next to the Phanerogams stand Selaginella ( Fig. 3o3), 

 Lj'copodiuni (l"ig. 357), ami similar plants, \\-ith stem, 

 leaf, root, and even struetnres answering to rudimentary 

 flowers. A little further removed come the true Ferns 



