lo ORCHIDS 



Orchids as Town Plants. 

 flowers expand. They are so delicate in texture that they 

 are damaged by the shghtest fog, while obstruction of the 

 light has the effect of so altering the coloured kinds that 

 they are with difficulty recognised, and do not afford 

 satisfaction to either grower or owner. 



On the other hand, the cool-growing and winter- 

 flowering sections of the genus Cypripediiim are rarely 

 damaged to any extent, and when once opened the flowers 

 last in perfection for many weeks, and yield a goodly dis- 

 play at Christmas and after. The majority of Orchids 

 being spring- and summer-flowering subjects, there is little 

 difficulty at those seasons in supplying the necessary con- 

 ditions for their successful culture. Those interested in 

 this particular phase of the subject will find some detailed 

 information under Cypripedium. 



Insect and other Pests. 



By far the greatest number of pests infesting Orchids 

 belong to the class Insecta, or Insects. These include 

 Cockroaches, Thrips, Mealy Bug, Scale, and Aphides 

 (Greenfly and their allies), &c. Thrips being very minute, 

 may escape attention for a time ; but the foliage 

 soon gives evidence of their attacks in the young leaves, 

 ^which discolour owing to the constant sucking of the 

 parts by the insects. Cockroaches are more destructive 

 to Orchids than is commonly supposed. The fact is that 

 being nocturnal their depredations are not as readily 

 traced. They attack the flowers, and if not trapped or 

 poisoned, soon disfigure a large number of promising 

 blossoms. Nor is it only the Common Cockroach that 

 the Orchid-grower has to fear. Of late years many 

 exotic species have been introduced into our 'plant-houses 

 with importations from abroad. 



The above constitute what may be termed general 

 insects likely to be found in any plant-house ; there are, 

 however, one or two other insects to be noticed hereafter 

 that confine their attention to certain genera of Orchids — 

 the Dendrobium Beetle {Xyleborus perforans) and the 

 Cattleya Fly [Isoscnna orchidearwn). 



With the exception of Scale and Mealy Bug, the 

 Cockroaches, and the beetle just named, all the other 



