2 STEWART MACDOUGALL—ON THE LIFE-HISTORY 
Whether such new species on issuing continue to live and 
gain a footing will depend on climatic and other reasons. 
Our purpose at present, however, is not to discuss the 
possibility of the acclimatisation of such insects as live in the 
open, but rather to emphasise the likelihood of damage and loss 
consequent on the presence of new injurious species of insects 
introduced with such plants as orchids, which are protected 
under glass and kept in a temperature resembling that of their 
native habitat—such surroundings favouring the chance of the 
parasitic insect obtaining a foothold. 
One such imported orchid-pest—unfortunately now only too 
well known in our orchid-houses—is a species of Xyleboraus which 
is injurious to the genus Dezdrodium. More than once I have 
had the attacked pseudo-bulbs sent to me with the insect iz 
sitz, in all stages of development, the last case being one of an 
attack on Dendrobium eburneum from an orchid-house at 
Pitlochry, Perthshire, the plants having been supplied by a 
dealer in the middle of England. 
Another such pest (also coleopterous) is Baridium aterrimus, 
a native of the Straits Settlements. I have received it along 
with damaged orchids from Penang, where it is especially 
harmful to Cypripedium and Saccolabium. There is at least 
one record of the presence of Baridium in England, a specimen 
having been determined by Mr. Waterhouse of the British 
Museum. This specimen was taken at Torquay on a species 
of Phalenopsts. 
A third pest whose capacity for destructive work makes it 
much to be feared is Dzaxenes dendrobit, the subject of this 
notice. Through the courtesy of Mr. Waterhouse, I am informed 
that since 1894 at least eight specimens of D. dendrobii have 
been sent to the British Museum from different parts of England 
and Scotland for determination. 
Late in December, 1896, I was asked to visit an orchid-house 
in Midlothian where a number of the plants had been ruined by 
some agency or other, insects being suspected. Attracted by 
discoloured patches on the pseudo-bulbs of some of the plants, I 
cut these open, and in each case found the larva of a longicorn 
etle. 
The larvze were of all sizes from very tiny up to evidently 
