136 TfiANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



insects are able to maiatain themselves in the growing wood of 

 large healthy trees, and when these occur in moderate numbers 

 they inflict only such wounds as are easily healed, corresponding 

 to mere scratches in the human skin. Under some conditions, 

 these insects increase abnormally, and then thousands of acres of 

 timber may be killed off. As the bleeding from many small 

 scratches may drain the human body of blood when they are 

 kept constantly open, so the boring of thousands of beetles, 

 insignificant individually, may weaken even the forest giant ; and 

 when this occurs, when there is no longer a healthy, resistant 

 tissue, then another host of other species steps in, adds to the 

 injury, and paves the way for yet further armies, leaving only a 

 dead stick with bare branches, sooner or later prostrated by a 

 storm, and then slowly reduced to dust by yet other agencies, 

 insectile, fungous, or microbic in character. It is the alteration 

 in the normal conditions of a virgin forest which the Forest 

 Officer, on making his appearance, brings about that renders 

 them more susceptible to insect attacks, and makes the study of 

 their life-histories of such importance. It is the certain conviction 

 that in proportion as scientific forestry progresses in India, 

 and more and more of our woods are treated on true sylvi- 

 cultural lines, so will the attacks of devastating insects make 

 themselves more and more felt, that leads me to endeavour to 

 obtain as many recruits as possible in the study of this very 

 important, but much neglected, branch of Forest Science. 



Collecting Aj)paratus. 



It will be first needful to consider what implements are 

 necessary to enable us to prosecute our campaign with success. 

 An examination of Entomological Catalogues presents to us a 

 diversity of apparatus, much of which is far above the purchasing 

 means of the average collector, whilst being at the same time far 

 from necessary. The collecting materials essentially required 

 may be of the simplest. Pill-boxes, small glass tubes, and a 

 stout glass pickle or jam jar should accompany the collector in 

 the field, and in addition, if it is required to collect Lejndoptera 

 (butterflies and moths), a stout net. 



Pill-Boxes. 



Pill-boxes should be preferably glass-topped. They can be 

 obtained in nests consisting of four boxes, one fitting within th 



