BEAUTIFUL FERNS. 
143 
frond is common in many undeniably genuine Aspiema: and 
since Diplazium, with double involucres placed back to back on 
the same vein, is inseparable from A splenium, it is by no means 
impossible that Scolopendrium and Camptosorus should be thought 
to have no better claim to rank as genera. 
Probably the earliest notice of the walking-leaf is in Ray’s 
“ Historia Plantarum,” vol. ii., p. 1927, published in 1688. It is 
there called “ Phyllitis parva saxatilis per summitates folii pro- 
lifera.” Other early accounts may be found in the “ Species 
Plantarum ” of Linn/EUS and of Willdenow, and in the second 
edition of Gronovius’s “ Flora Virginica.” In the latter work it 
may be seen that Gov. Golden long ago described the auricles 
as being “ also often acuminate.” 
A second species, with membranaceous fronds acute at the 
base (C. Sibiriais), occurs in Northern Asia, but is apparently 
very rare. 
