GENUS XL 
CETERACH, Willdenow. 
SCALE FEBN. 
GEN. CHAK Sori elongate oblong or linear, all but 
the lowest on each pinna attached to the anterior side of 
the anterior venules, hidden amongst densely imbricated 
chaffy scales. Indusium obsolete. Veins forked or pin 
nate ; venules anastomosing near the margin, the lowest 
posterior one soriferous on the side next the rachis. 
This genus being without an tndusium might seem to 
belong to the Polypodies, but the position of the recep- 
tacle on the side of the venules determines its affinity to 
be with the Atpleniea. 
The generic name is a modification of Chetherak, ap- 
plied to this plant by the Arabian and Persian phy- 
sicians. 
1. Ceterach officinarum, Willdenow. Common 
Scale Fern Fronds sinuate- pinnatifid ; segments oblong- 
obtuse, entire or lobed on the margin. 
CETEBACH OFFiciNARtJM, Willdenow ; Bab. Man., 415: Florlgr. 
Brit, iv., 81. : Newm. 293: Hook and Am. Fl. 566. GKAMMITIS 
CETEBACH, Swartz: Franc 20. SCOLOPENDKIUM CETERACH, 
Symons: Sin. En<*. Fl. iv., 315: Eng. Bot. t. 1244. ASPLENIUM 
CETEBACH, Linnasus. XOTOLEPEUM CETEKACH, Newman, Brit. 
F. 9: App. v. GYMJJOGRAMMA CETEBACH, Sprengel. 
