ON GENERA AND SPECIES. DO 



Presl by placing Matonia in alliance with Cyathea, with 

 which in habit and even in technical character no generic 

 affinity is traceable. 



In his general arrangement he follows, with a partial 

 exception, the sequence of Presl, arranging the whole 

 under two sub-orders, Gleicheniaccce and Polypodiac&e, the 

 latter consisting of twelve tribes, beginning with Cyatliea, 

 including Hyinenophyllum, and ending with Acrostichum. 

 With regard to Asplenium, Polypodium, and Aspidium, he, 

 in a great degree, follows Mettenius and Fee's arrange- 

 ment and descriptions of Acrost ichum. 



From what has now been stated it will be seen that, 

 although Sir W. Hooker bestows great praise on his con- 

 temporaries, he nevertheless adopts but few of their genera, 

 thus making it appear that but little advance has been 

 made in our knowledge of the natural habit and anato- 

 mical structure of Ferns since the time of Sprengel (1827). 

 He, however, finds himself compelled to divide his large 

 genera into sections, which are equivalent to the genera of 

 authors ; indeed, it is only by the sections that we are 

 saved the labour of wading through 200 or 300 species in 

 order to find out a single individual . 



The following is a tabular view of the sequence of 

 the tribes and genera as arranged in the " Species 

 Filicum " : 



ORDER I. FILICES. 



Sub-Order I. GLEICHENIACEJE. 

 Gen. 2. Platyzoma, Gleichenia. 



Sub-Order II. POLYPODIACE*:. 



Tribe I. CTATHEJ:. 

 Gen. 3. Cyathea, Hemitelia, Alsophila. 



