94 



FAMILIAR LESSONS IN BOTANY. 



matured, this, partly absorbed and partly thrown off by 

 decay, becomes simply a ring, called anniihis (Fig. 125). 



Fig. 122. 



Fig. 123. 



Fig. 1^4. 



246. Ferns have light graceful leaves which we call 

 fronds. When young they are curled, circinate (Fig. 126), 

 and expand by unrolling. Their c<?/;o re-cases or seed-ves- 



FiG. 125. 



Fig. 126. 



sels are situated on the back of the fronds, as you saw in 

 the cut showing sori, and are arranged differently in dif- 

 ferent species. 



247. The genus equisetacea?, horse-tail, contains numer- 

 ous species. They consist of leafless, jointed stems, erect, 

 hollow, and ridged. The spores of the equisetaceae are con- 

 tained in scales forming the inflorescence, which appears in 

 the form of a terminal spike (Fig. 127). 



248. The mosses are composed of cellular tissue entirely, 

 and are furnished with a tlicca supported on a slender stalk 

 called seta (Fig. 128). The tuft of leaves from which the 

 seta or stem springs is called a periclicetium (Fig. 129) : a 



246. What are ferns? Fronds? Spores? Sori? 



247. What are eqnisetaceoe ? Describe them. Where are their spores 



248. What is the seta ? Per ihnetium ? 



