L32 Walking Leaf 
undulate or irregu.ar or rarely incised: midribs prominent be- 
neath: surfaces glabrous: color deep, lustrous green, or yellow- 
ish-olive in age or in plants exposed to the sun: texture cori- 
aceous or subcoriaceous. 
Venation pinnate, anastomose: marginal veinlets largely free. 
Sori linear, straight or curved, variously placed along veins, 
some solitary, some confluent with ends of others, some conni- 
vent, usually outwardly, or simply faced in pairs: indusia whitish, 
delicately membranous, undulate at margin, attached at sides 
or around outer ends of areolz or at leaf’s margin to free veinlets, 
those next midrib opening toward it, many of the outer opening 
toward each other in pairs. 
Spores ovoid, with winglike pellucid crenate margin. 
Habitat. Limestone, gneiss, granite, quartzite, sandstone, 
shale, and serpentine.* On cliffs, boulders, etc.,f usually on 
shaded sloping rock coated with mossy earth. Over this the 
leaves stretch, crossing one another: in the interstices the pro- 
liferous tips of new leaves are inserted. 
Range. Maine and southern Quebec to Minnesota, south to 
Georgia, Alabama, and Kansas. 
Camptosorus rhizophyllus (Linneus). Link, Hort. Berol. 2: 69. 1833. 
Asplenium rhizophylla. Linneus, Sp. Pl. 1078. 1753. 
Tue leaf first produced by the plant springing from the 
proliferous tip of a mature leaf of Camptosorus rhizophyllus 
often, if not always, represents a higher degree of leaf-develop- 
ment than the first produced by the plant springing from the 
prothallus. The blade of the latter leaf is either spatulate, ob- 
cordate, or obreniform: if spatulate, a leaf with an obreniform 
* See Fern Bulletin, 8:92, 1900. Also D. C. Eaton, N. Am. Ferns, 1:56. 1878. 
+In the Jimestone region of Vermont I have seen this plant lining the mouth of an 
old well. 
