THE FERNS OF NORTH-WESTERN INDIA . 
7 
The theory underlying all this restriction or reduction of species 
seems to be that recently observed plants, however apparently 
distinct, are likely to be mere varieties of previously known and 
described species. But a variety must surbly be a variation proved to 
have originated from a known plant, and not merely a different plant 
which botanists think resembles a well-known plant, and, from dislike 
to increase the number of species, choose to call a mere variety of it. 
I am well aware that there are hundreds of cultural varieties of 
f erns __ European chiefly — and that these, having been propagated 
from plants found wild, retain their characters permanently when 
cultivated, or diverge even further from the type. But such 
varieties are for the most part sports, or monsters in appearance, and 
no one thinks of setting them up as species ; and botanists do not even 
enumerate them under the species from which they are known or are 
supposed to have originated. Fern-fanciers, on the other hand, would 
probably cease to take an interest in them if they were recognised by 
botanists as species. Such sports are rarely found in India, and when 
met with are treated *as sports not named as varieties. The so-called 
varieties of Indian ferns are serious entities, with no eccentricities of 
form or habit, and, were it not for slight or fancied resemblances in 
them to previously described species, there seem to be no good reasons 
why they also should not be favoured with full descriptions and specific 
names. Differences of mode of growth and venation are surely good 
specific distinctions ; and yet we find plants so differing grouped under 
the same specific name, and one called a variety of the other on merely 
fanciful grounds. There is sometimes doubt as to the separate entity of 
species described in the books, because the nature of the rhizome, has 
not been observed and described. For this collectors are of course 
partly to blame ; but in many cases authors are silent as to the rhizome, 
and seem to think it a feature of no importance. An isolated plant with 
a woody root-stock, perhaps nearly as thick as one’s wrist, of slow and 
almost secular growth, and which is erect, or merely decumbent, and 
throws up fronds from the apex in a tuft, and, if decumbent, 
dies off behind, while it continues to grow slowly forwards, is of a 
totally different nature from a fern which has a thin, perhaps succulent* 
quickly growing and widely-creeping and branching rhizome ©r sar- 
mentuMj which throws up fronds singly at greater or less intervals 
