THE WALKING FERN AND HART’S-TONGUE., 271 
the legs of that animal. There are about half a dozen 
species. The scientific name of our plant has been 
frequently changed. It was long known as Scolopen- 
drium vulgare or S. officenarum, later it was called S. 
Scolopendrium, and still later Phyllitis Scolopendrtum. 
Those who are interested in the plant rather than its 
name will prefer to call it by its best known title, as 
we have done, until the makers of nomenclature decide 
upon a name that shall not be changed, 
