THE FERNS OF NORTH-WESTERN INDIA. 319 



from the normal, clue probably to difference of altitude or climate, but 

 insufficient to prevent identification or to warrant separation as a species. 

 To such "forms '' separate numbers are not given. So-called varieties, 

 when distinct enough from the so-called types to be separately describ- 

 ed, and, so far as I know, constant as to characters, are given as species 

 in the absence of any good reason why they should be given any less 

 important a position. Most of these were originally named or described 

 as good species by the collectors of them, but have afterwards been 

 reduced by authors who have never seen them growing in their native 

 habitats. In no such instance does there appear any evidence of 

 origination by variation from another hnown species ; and the place as 

 a variety seems in most cases to have been assigned either from a fancied 

 resemblance to an old species, or merely because the plant, being of the 

 same genus,has been observed or discovered, and described, subsequently 

 to the date of the description of the so-called type plant. Such plants 

 have been ranked as varieties long enough, and, having successfully 

 passed a period of probation, may now be promoted to specific rank. 

 As to most of them, the difhcultv seems to me— not how to distinguish 

 them from their so-called prototypes, but — how to think and write of 

 them as being near these. Admitting, for the sake of argument, their 

 origin by variation, they have become good and permanent species 

 showing no tendency to revert, and ought to be treated as species. 



In two notable instances numerous varieties of plants have been setup 

 by authors as growing in India, the types of which are expressly stated 

 as not having been found in that region. Thus, after giving an elabo- 

 rate description of Asplenium {Athyrium) Fili.v-fcemina, Bernh. [forma 

 europcBo), apparently by himself, Mr. Clarke goes on to say that 

 the typical form has not exactly been got in the Himalaja, and to give 

 no less than seven varieties of ft, which have been got there, with a 

 short description of each. In this case Colonel Beddome, in his 

 " Handbook," follows Mr. Clarke almost verbatim, giving all seven 

 varieties. At least two of these, A. Schimperi, A. Br., &nd A . pedi- 

 natum, Wall., which have widely creeping and branching rhizomes or 

 sarmenta and distantly springing fronds instead of the erect caudex and 

 fasciculate vernation of A. FilLv-fcemina, have been recognised as good 

 species by Colonel Beddome in the Supplement to his " Handbook." 

 In the other instance, that of Naphrodium (Lastrea) Filix-mas, Rich., 



