68 CAMPTOSORUS RHIZOPHYLLUS. —- WALKING-LEAF, 
more reticulated, or net-veined than the maturer and fruitful 
ones (Fig. 2). Indeed it is our experience that when a frond is 
abundantly fruitful, the veins are often wholly free. It may be 
also remarked that in the enlarged drawing at p. 75 of Mr. 
Williamson's “Ferns of Kentucky,’ the veins are all wholly 
clear of each other. 
Asplenium pinnatifidum is remarkable for its fertility. Often 
early formed and small fronds are as completely covered with 
sporangia as larger and more recent ones, and it has little dispo- 
sition to make terminal buds; while the Camptosorus is compara- 
tively a sparse-fruiting fern, and makes up for this by its power 
of increasing from terminal buds (whence comes its name rhzzo- 
phylum). t would be curious if it should ultimately prove that 
the one form has been evolved from the other by a sort of dif- 
ference of opinion, as one might almost say, as to the best 
methods of reproduction, and that the greater divarication of the 
veins in the walking-leaf (which is really all the difference) is a 
mere incident in the reproductive question. 
The Camptosorus under its older names has been long known 
to botanists, having been noticed by Ray, Morison, Plukenet, 
and others of the early English authors of the first part of the 
eighteenth century. Gronovius had specimens sent to him 
both by Clayton from Virginia and Colden from New York. 
Michaux found it “not abundant” from “Canada to Tennessee.” 
Dr. Gray says its home is from “west New England to Wiscon- 
sin and southwards.” The writer of this has found it abundantly | 
on the rocks running from east to west across the state in South- 
ern Illinois, and Professor Lesquereux found it in Arkansas. 
EXPLANATION OF THE PLATE.—1. Complete plant. 2. Fertile frond. 3. Rooting point of 
one frond. 4. Barren frond conspicuously netted-veined, 
