70 



THE BOOK OF CHOICE FERNS. 



very few exceptions, Trichomanes, Hymenophyllums, and Todeas, might, 

 with advantage, be grown in a temperature allowed, during the winter, to 

 fall within a few degrees of freezing-point ; for, as he justly remarked, 

 even the kinds indigenous to tropical countries are generally found in 

 mountainous parts, where they usually grow at high elevations. Many of 

 them will even bear freezing. It is on record, for instance, that in Messrs. 

 J. Backhouse and Son's nursery, at York, Trichomanes mclicans occasionally 

 stands a temperature below zero. We also know that, besides the above- 

 named species, Todeas and Hymenophyllums have, without visible injuries, 

 withstood a temperature of 14cleg. below freezing-point at Messrs. J. Yeitch 

 and Sons' Chelsea establishment, where, for a whole fortnight, they were 

 frozen into a solid block of ice. When under the influence of the thaw, 

 the fronds gradually recovered their former positions, and, as year after year 

 passed by, it was ascertained that these plants had not suffered from 

 the rigours of the temperature to which they had been exposed. Until 

 the winter of 1879-80, during which the above-stated incident occurred, 

 the " Cool Filmies " had always been covered over in cold weather ; but, 

 there being no hot-water pipes in the places where these were planted, 

 and being much exposed to cold winds, it was found impossible, with all 

 clue exertions, to keep the frost out. One may, therefore, judge of the 

 anxiety of all concerned in their welfare during that length of time, and also 

 the pleasure experienced when, after the ordeal was over, it was seen that 

 the plants had not suffered in the least. After a very short period they 

 started into fresh growth, which proved more vigorous than that produced 

 by other plants of the same kinds subjected to artificial heat. It need hardly 

 be added that since that time the "Cool Filmies" do not receive any more 

 covering during the winter. 



While at Upper Grosvenor Street, where the atmosphere was by no 

 means congenial to them, it was only by dint of constant attention carefully 

 bestowed upon them by a most diligent observer and devoted admirer, that 

 these plants were kept in such perfect condition. This justly- celebrated 

 collection is now the property of Kew Gardens; it was generously presented 

 to that institution in 1888 by Mr. Stuart Forster, who inherited it at 

 the death of his father, in March, 1886. There to this day may be seen 

 in a special case in the cool-house, among the Forster Collection, but greatly 



