622 



THE BOOK OF GARDENING. 



Other insect pests which do considerable damage to Orchids 

 are the Cockroaches. These are most difficult to eradicate when 

 thoroughly established, as the colonies are usually in very inac- 

 cessible places, and the eggs so well protected as to be out of 

 the reach of insecticides. These not only destroy the vital parts 

 of Orchids, but also entirely disfigure the flowers. For Cattleya 

 blossoms in particular Cockroaches betray a marked partiality, 

 and in a single night will destroy what has taken the grower 

 months to achieve. Cockroaches are so readily introduced, either 

 in importations of new plants, or even in the clothing, that 

 the gardener can hardly be too careful, and should their 

 presence be detected he should at once take active measures to 

 deal with the pest. Our plant-houses afford the insects the 

 warmth that is absolutely necessary to their welfare ; and no 

 w^onder, therefore, is it that once introduced they take a lot of 

 ousting. Phosphorus paste spread upon bread-and-butter is as 

 good a trap as anything, and wnll kill large numbers. Cock- 

 roaches are nocturnal in their habits, and in the daytime are 

 seldom visible. 



At one time growlers of plants had but one species to contend 

 wnth — Pej'iplaneta orientalis — an insect which holds its midnight 

 revels in our kitchens, causing them to have a most disgusting 

 smell. To-day the number of species found has been consider- 

 ably augmented, due mainly to the way in which the importation 

 of plants has increased. One of the commonest of these 

 Cockroach newcomers is P. australasice^ a handsome insect. 

 This has established itself in this country, and promises to 

 become still commoner in the future. Unlike P. orientalis^ it 

 is winged in both sexes. In colour it is red-browii, with a 

 yellow streak along the costal margin of the fore-wing at the 

 basal half. The pronotum is black, and has a distinct yellow 

 margin all round. P. australasice is altogether larger than the 

 so-called "Black-beetle," and a generally showner insect. Though 

 the specific name suggests Australia as the native country of this 

 pest, yet such does not seem to be the case. Large numbers of 

 the insect have been taken in public gardens giving place to 

 Orchids, &:c., and from many private collections it has also been 

 recorded. All Cockroaches are inimical to plant-life, and should 

 be seriously regarded by the gardener who values his precious 

 charges. 



Belonging to the Heinipte?'a Heteroptera are the plant-bugs, a 

 group of insects whose ways are not so wxll understood by the 

 gardener as they should be. Of late one of these creatures 

 has been adding to the troubles of the Orchid-grower by inflicting 

 damage upon Dendrobium foliage. The insect responsible for 

 this mischief is known as Phytocoris militarise a near relative of 

 the objectionable-smelling creature found upon Raspberries and 

 the like. It is another of those insects wnth which an interchange 



