HISTORY OP INTKDDUCTIOIT OP EXOTIC PERNS. 7 



Fems existing at that period in British gardens, 

 and not included in the " Hortns Kewensis." 

 Speaking from my personal recollection of the im- 

 portant collection of plants in the Hackney Nursery, 

 as it existed in the year 1825-, I think it contained 

 about a hundred good species of exotic Ferns ; but I 

 can obtain no earlier catalogue than one published 

 in 1849, in which two hundred and fifty-one are 

 enumerated. 



In the year 1822 I found the collection of Perns at 

 Kew extremely poor, especially as regards Tropical 

 species, very many of those introduced ia previxjus 

 years having been lost, and very few new ones added. 

 Any person who remembers the hothouses in existence 

 forty years ago, will have but little difficulty in 

 accounting for the falling ofiF of the Pern collection. 

 In those days hot-water pipes were unknown, and 

 the houses were exclusively heated by means of 

 brick flues, too often imperfectly constructed, and 

 the excessively dry and ungenial atmosphere thus 

 induced was quite unsuited for the good cultivation 

 or even for the mere preservation of these moisture- 

 loving plants. Nearly all the North American species 

 enumerated in the " Hortus Kewensis " were growing 

 very finely in a north border, and most of the Madeira 

 species were also in existence; but, including these 

 and the few added since 1813, I cannot estimate the 

 entire Kew collection of exotic Ferns at that period 

 at more than forty species. 



Between 1813 and 1846, when my first Catalogue 

 of . the Ferns at Kew appeared, no reliable list 

 was published in this country. Several, however, 

 were brought out by Continental botanists, which 



