38 Ferns and Fern Culture. 
frost without injury, although it is unquestionably better 
to keep the temperature from falling below 35°. The 
Todeas have upright stems, and in time form miniature 
Tree-ferns. They may be planted in pots, pans, or rock- 
work. The Hymenophylle and Trichomanes are nearly 
all creepers. Their thin rhizomes spread freely, and 
necessitate their being in pans, or rockwork, or on the 
stems of Tree-ferns. For Wardian cases these are un- 
equalled by any other class of plants. 
HYMENOPHYLLUM TUNBRIDGENSE. 
(The Tunbridge Filmy Fern.) 
If the atmosphere of the house or frame can be densely 
laden with moisture, so as to keep the foliage always 
damp, the Filmies will not require watering overhead. 
This may sometimes be accomplished by sprinkling 
plenty of water on the paths, walls, stages, and rock- 
work. If this is not sufficient they will require dewing 
overhead with the fine rose of a syringe. Sometimes 
this causes discolouration of the foliage. When it does 
it is probably the result of some injurious element in the 
water. Only soft, tepid water should be used, and with 
