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time and pressure and heat, into the black shining coal seams, 

 which now reveal their history and treasures tO' our curious eyes. 

 Plants are divided by botanists intO' two great classes, the 

 flowering and flowerless, or, as botanically expressed, phaner- 

 ogamic and cryptogamic. In the one class flowers are pro- 

 duced which are followed by seeds formed on the parent plant. 

 In the other there are no' parts produced corresponding to 

 flowers. The stem bears leaves only which have the property 

 of forming for the purpose of reproduction a peculiar form of 

 germ bud, to- which the name of spore has been given. To this 

 class ferns belong. They are distinguished from other plants 

 in the same class by the nature and position of the cases in 

 which the spores are contained. These spore cases are formed 

 on the back or margin of the leafy poxtion or frond, and in 

 some on spikes. The vegetative organs of ferns are the root, 

 the stem, and the frond or leafy part. The roots are always 

 fibrous, and in their younger portions are covered with fibrils or 

 soft hair-like bodies, which give them a downy appearance. 

 The stems are often erroneously called the roots, and assume 

 twO' forms called the caudex and the rhizome. In the caudex 

 or caudiciform stem the fronds rise from the termination of the 

 axis of growth either in a single series or in a kind of crowned 

 whorl, so as to form a terminal crown. The young fronds in all 

 cases spring from the inner side of the previous fronds, their 

 bases becoming united, sO' that the older part of the stem con- 

 sists of a combination of the axis of growth, with the basis of 

 the fronds developed from it. In British ferns this is well seen 

 in old plants of Lastrea Filix-mas. In the Rhizomiform stem 

 the fronds, which are more or less scattered, are developed from 

 the sides of the axis of growth, which appears to be in advance 

 of the last-formed fronds. The Polypodium vulgare forms a 

 good example of this mode of growth. The leaflike organs of 

 ferns are called fronds. The frond differs from the leaf of 

 the flowering plant in that it actually bears on its surface the 

 parts known as fructification, which the true leaf does not. 

 The fronds of almost all ferns are in their incipient condition 

 coiled up inwards towards the axis of development, forming a 



