CETEIMCH. .W.) 



GENUS TX. 



Caudex brief, erect, and tufted. 



Fronds j)innatifid, coriaceous, densely scaly beneath, with 

 imbricated chaffy scales. Sori linear oblong, obsoletely indusiate, 

 the receptacles lateral. Veins forked from a central costa. 



The character of Ceterach is midway between Asplenium and 

 Gymnofjramma. 



The late illustrious Sir W. J. Hooker, in "Species Fillcum," 

 places this solitary Fern with Asplenium in the sub-genus 

 Hcmidicfijum. A host of botanists give the rank of Ceterach, 

 whilst others have united it with Seolopendrium, Vittaria, 

 Gymnopteris, Grammitis, Gymnogr amine, AcrosUchcm, Bleeh- 

 num, and Polyi)od'mm. 



Sir W. J. Hooker, in his large genus Asjilenium, numbering 

 three hundred and five species, divides them into sub-genus 

 1. — Thamnoptcris , seven species, A. Anstralasicmn being an 

 example; 2. — Eiiasjilenium, two hundred and seven sj^ecies, 

 A. marinum, A. lucidum, A. hidbtferum, A. trichotnanes , and 

 A. viviparum being examples; 3. — Athyriwn, twenty-nine 

 species, A. filix-fcsmina and A. nnihrosum being examples; 

 4, — Eudiplazitim, fifty-one species,^, striahim being an example; 

 5. — Anisogonium, seven species,^, esculentum being an example; 

 and 0. — Hemidictyum, four si^ccies, A. marginatum and A. 

 ceterach being examples. 



Mr. Thomas Moore, in "Index Filicum," retains the genus 

 Ceterach, and does not agree in uniting the Mediterranean 

 form aureum with our British ojficinarnm, notwitlistanding 

 that my namesake, the Rev. R. 'J\ Tiowe, has found every 

 variety of form and size uniting tlie two. 



VOL. II. 3 B 



