

Fig. 118. A fern (Aspidinm), showing three large branching leaves coming from a 

 horizontal subterranean stem (rootstock); young leaves are also shown, which 

 show circinate vernation. The stem, young leaves, and petioles of the large 

 leaves are thickly covered with protecting hairs. The stem gives rise to numerous 

 small roots from its lower surface. The figure marked .? represents the under sur- 

 face of a portion of the leaf, showing seven sori with shield-like indusia; at 5 is 

 represented a section through a sorus. showing the sporangia attached and pro- 

 tected by the indusium; while at 6' is rei)resented a single sporangium opening 

 and discharging its spores, the heavy annulus extending along the back and over 

 the top.— After Wossidlo. 



