THE WALKING FERN AND HART'’S- 
TONGUE. 
| NE of the good points about 
the study of ferns is that the 
subject can never be quite 
exhausted. There is always 
something more to be 
learned or a species yet un- 
discovered in the locality to 
search for. Some _ plants 
have the faculty of eluding 
one for years and then 
appearing in some out-of-the-way nook, while others 
must be made the objects of special expeditions if one 
would obtain them. In the latter category may be- 
placed the two plants to be discussed in this chapter. 
In addition to being uncommon or rare, their peculiar 
forms make them easily overlooked unless the collector 
has once seen them growing. 
The Walking Fern. 
The very name of the walking fern (Camptosorus rhiz- 
ophyllts) sounds sufficiently attractive to arouse interest 
in those who ordinarily are not fern collectors. Com- 
paratively few, however, have seen it growing and the 
majority are inclined to hold curious ideas regarding it. 
One collector told the writer that he fully expected to 
