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which is then covered with a glass plate. In Penang 

 Gardens a Fern rockery has been made by collecting stones 

 chiefly of sandstone or granite, the older and rougher the 

 better, and arranging them under a small wood of trees. 

 Here certain Ferns have done exceptionally well, and espe- 

 cially the stiff leaved Ferns such as Humata which requires 

 a certain amount of dryness. The rare Pteris Dalhoustae 

 is growing here finely. But limestone rock seems to suit 

 the Ferns better than sandstone or granite. 



Pests. — There are not many pests on Ferns. The most 

 troublesome being a caterpillar which spins together the 

 ends of the fronds and destroys them. It chiefly attacks 

 the Nephrodiums and Ahgiopteris and should be destroyed 

 as soon as it is seen. The Maidenhairs if neglected are 

 liable to attacks of Coccus (white blight) and should be 

 cleaned if necessary with tobacco water. 



Some Exceptional Ferns. 



A few Ferns which possess somewhat peculiar habits 

 may be noted. The water Fern Ceratopteris thalictroides 

 is a truly aquatic plant and is best grown in ponds or 

 ditches, it is said to be biennial, whether this is so or not 

 does not seem clear but it certainly has the habit of dis- 

 appearing entirely from the ditches in these gardens and 

 then after some months reappearing in abundance. 



Ophioglossum pendulum the long pendent Adder 's 

 tongue Fern usually prefers to grow in a plant of the 

 Elk's-horn Fern, Platy cerium, where it pierces the large 

 supporting fronds of this plant and hangs down below it. 

 It appeared on one occasion on a Date-palm in the Gardens 

 growing on the vegetable remains on the trunk and in soil 

 brought up by Termites, and eventually it quite draped the 

 trunk of the tree with its long green ribbon-like fronds. 



The little Adder's tongue Fern, Ophioglosmm rmdi- 

 caule is not easy to cultivate but on occasions when speci- 

 mens have been brought from other part of the Peninsula 

 for the Herbarium, it has almost invariably turned up 

 sporadically in the gravel paths, apparently from spores 

 drifted away from the dried plant. 



Dtivallia tripliylla though by no means a rare plant in 

 the Peninsula was for a long time very rare in collections 

 of dried ferns and was not known in cultivation at all till 

 it was sent from the Botanic Gardens, in Singapore. The 

 reason for that was that it grows habitually on the topmost 

 branches on the loftiest trees, wliere it was quite inacces- 

 sible. It is however to be obtained from fallen branches 



