114 STUDY OF COMMON PLANTS. 



X. FERNS. FILICINE^E. 



MATERIAL REQUIRED. 



Shield-fern, Aspidium cristatum, Swartz, gathered in summer when the 



fructification is fully developed. 

 Similar specimens of maidenhair, Adiantum pedatum, L., brake, Pteris 



aquilina, L., spleen wort, Asplenium Filix-fcemina, Bernh. 

 Representatives of other genera of ferns that are procurable, such as 



Cystopteris, Woodwardia, Osmunda, Dicksonia, etc. 



SHIELD-FERN. Aspidium cristatum, Swartz. 



General Characters. 



I. Record first what you have observed as to the habits 

 and habitat of the plant. Does it grow in moist or dry 

 ground? in shady places or in the open? How do its 

 habits compare with those of other ferns, as regards choice 

 of soil and surroundings ? l 



II. Notice the parts of the plant. 



1. The underground stem, from which arise 



2. Large, compound leaves, fronds, and 



3. Roots. Observe their origin, form, and structure. 



The leaf is the most characteristic part of the fern, and is 

 to be studied in detail. Notice 



1 Cf. Underwood, Our Native Ferns and their Allies. 



