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by these difficulties, but all who have the time should try some 

 experiments, for though wonderful progress has been made in 

 hybridising by Messrs. J. Veitch & Sons, there is still an ample 

 field for investigators, and many gentlemen have turned their 

 attention to the matter in recent years.. In any attempt of the kind 

 care must be exercised to prevent the intended seed-bearer being 

 fertilised from any other source, both before and after the desired 

 cross has been made. This may be effected by tying a piece of gauze 

 round the flower when it is expanded, also removing its own pollinia. 



CULTIVATORS' ENEMIES. 



Orchidists have abundance of enemies to contend with, for the 

 plants are subject to the attacks of many insects ; but in this, as in 

 other cases, prevention is better than cure, and a continual watch- 

 fulness for the first appearance of these pests and the adoption of 

 prompt measures will save endless trouble. It is important to insure 

 that the plants purchased are thoroughly clean, and if there be any 

 doubt on the matter they should be well washed with tepid water 

 and a small quantity of softsoap, sufficient to discolour the water, 

 this being especially necessary for imported plants, the roots of which 

 should also be washed in clean water. Orchids are subject to the 

 attacks of most insects which infest other plants, such as green fly, 

 red spider, thrips and s 'ale of several sorts, and mealy bug ; while 

 snails, slugs, woodlice, ants, and cockroaches also cause much trouble 

 if allowed to become numerous. It is not difficult to keep a small 

 collection clean, but where large numbers of plants are grown it 

 requires constant care ; and in some establishments it is the rule to 

 thoroughly clean the whole stock periodically, for delicate plantg 

 once a month. The frequent use of tepid water, softsoap in very 

 email quantities, or weak tobacco water is the best means of keeping 

 the foliage clean, applying the liquids with a sponge or camel's-hair 

 brush. Green fly and the thrips may be destroyed by fumigation 

 with tobacco or tobacco paper. Though this is commonly recommended 

 it is a dangerous expedient in the hands of beginners, for a strong 

 fumigation will often prove far more injurious than beneficial. It 

 should only be resorted to in extreme cases, and then it should be 

 given very moderately on several alternate nights ; choose a quiet 

 evening, have the house drier than usual, and if moveable blinds are 

 employed pull these down. Be careful to place the fumigator where 

 the hot smoke does not ascend directly under any plants, and do not 

 employ burning coal or coke, as the gases arising from these are very 

 injurious. Slugs and snails must be looked after closely, a little 

 bran being a good bait for theoi. A few cabbage leaves can also be 

 laid about on the stages, and frequently examined ; hollowed potatoes, 

 a little moss, and various other things serve as traps for woodlice. 



