274 ALLANTODIA. 



ranked it among the Nudi.sori. Mr. \V. Wilson was the first to direct my atten- 

 tion, in 1828, to the presence of a narrow involucre of an Anplenium, such as we 

 have figured it in the ' Genera Filicum,' and in the ' British Flora,' and M. Ft-e 

 has detected and represented a much more distinct involucre in the var. aiireum. 

 We have thus only the partially anastomosing venation, like th^t of Ilemidicfi/iim, 

 to depend upon ibr generic distinction. Our plant has, in habit, the closest 

 affinity with J.ipi altenians, Wall., wiiich latter, however, has free venation and 

 no paleaceous covering to the under side of the frond. Mcttenius maintains the 

 genus Ceterach, but he ignores the existence of an involucre (" sori laterales 

 indusiati: caiterum Asplenii'^ a.x\A refers Gymnof/ramme Capensis to the same 

 genus, as did M. Fee in his Gen. Fil., p. 206, where he says that "la presence 

 d'un indusiuni,toutefois tres-difficile a reconnaitre, et que cependant noussommes 

 parvenus u constater, les place parnii Ics Asplenipes"). Nevertheless, in the 

 " additions and corrections" of the same work, at p. 3(53, Fee suggests, most properly 

 according to his views, the sejiaration of the latter on account of the free vena- 

 tion, but denies the existence of an involucre in the true Ceterach ; " Ce que nous 

 regardions comme tel, n'est autre chose que la nerville receptaculaire renflv'e et 

 chargee des debris de pedicelles de sporangiastres fascicuk'e a leur base." In il- 

 lustration of this he refers to figures in a supplementary plate (t. 30), and 

 represents, from recent analyses, several sori both of C. officinarum and C. aureum 

 (C. latifolium, Fee), with what have every appearance of well-defined, true invo- 

 lucres of an J.splenium, but narrow — in short, such as we have ourselves seen and 

 figured, and such as Moore and Webb have described. Such an organ we cannot 

 therefore doubt exists, and every one must form his own opinion as to its real 

 nature and importance. Our largest and finest specimens of British //. Ceterach 

 are gathered in Ireland by Fred. J. Foot, Esq., and these have broader and sinuated 

 segments to the fronds ; but a more remarkable variety we fear we must only 

 consider it to be, is the Ceterach aureum* of the Canary Islands. 



2. Allantodia, Wall., Br. in part. 



{WaUich, PI. Asiat. Ear. t. 52. Hook. Gen. Fil. tab. 

 CXX. A. HeinicUctyum, Pr. Asplenium, Wall, Metten., Bl.) 



Sori involucrate, single, dorsal, attached to the primary 

 veins, oblong. Involucre dark-brown, subcoriaceo-membrana- 



* Unable to detect any sound specific character in this supposed species, I con- 

 sulted my val-.ied friend the Kev. R. T. Lowe, who sends me the following reply : — 

 " In my opinion, C. aureum. Cav. (Jspl. latifolium, Bory) , is not distinct as a species 

 from C. officinarum, W. When I first went to Madeira, in 1826, I was fully 

 primed for distinguishing the two ; and I experienced, consequently, no small 

 amount of puzzle and vexation at encountering continually plants which, from 

 their smaller size and other characters, could be referred to nothing but our Bri- 

 tish €'. officinarum, and yet possessed the toothed scales of C. aureum. I soon 

 found, however, that no dependence could be placed on one or other of the cha- 

 racters assigned to C. aureum, and 1 settled in my own mind, that the Madeira 

 plant, at all events, was nothing but the European C. officinarum, W., though 

 in size often verging towards, and in the more or less toothed scales agreeing 

 with, the so-called Canarian C. aureum. In Grand Canary, and especially in 

 Ilierro last year, I found myself equally unable to draw any line of distinction 

 between the two. On the north-west coast of Ilierro, in that wonderful district 

 called El Golfo, where the cliffs, receding from the sea, and clothed with noble 



