So THE CANADIAN ENTOMOLOGIST. 



little traversed field of tiseful work, which is open to the veriest tyro in the 

 study of insect life. In addition to this, many inaccurate statements have 

 been made and ofttimes repeated as to the life habits of common 

 injurious insects. Some of these errors have stood for years and have 

 only been disclosed by more careful observations being made on all the 

 stages, whether it was thought they were necessary or not. Instances of 

 such faulty work may often be found in printed records of the time, place 

 and method in which the eggs are laid, the condition and situation in 

 which winter is passed and the duration of the various stages.' Accuracy 

 as to every one of these facts is of the greatest necessity when devising a 

 practical remedy for those kinds of insects which do harm. A practical 

 remedy is one which will do the work aimed at — effectively, so as to pre- 

 vent damage to the crop; easily, so that people of ordinary intelligence 

 can apply it without danger of mistake, and cheaply, so that the applica- 

 tion of the remedy may not cost more than the value of the crop to be 

 saved. The best remedy for a given crop pest must mainly depend upon 

 how it will answer these three requirements, and the special work of the 

 economic, or practical, entomologist is to devise the best remedy possible 

 under varying circumstances. No remedy can be expected to give perfect 

 immunity from loss, any more than the best remedy in the hands of a 

 skilful medical practitioner can be expected to save every patient entrust- 

 ed to his care. In both cases there are many contingent circumstances 

 which may neutralize the effects of the best of remedies applied in the 

 best known manner. , ' • 



The foundation of all safe generalizations must rest upon as large a 

 mass of proved facts as possible. In entomology, as in every other 

 branch of knowledge, proved facts are wanting concerning very many 

 common objects. I know of no more fertile field of useful work in the 

 study of insects than that which deals with the life-history of any specie? 

 in its home, including particularly its method of adjusting itself to it£ 

 surroundings. Such facts as will be brought out in this work are now 

 grouped together and spoken of as the ecology of a species. Ecology (or 

 more properly QCcology, the word being derived from the Greek oikos, a 

 home) is as yet a rather unfamiliar word, but is so complete and express, 

 ive that it must surely soon come into more general use. A consideration 

 of the winter home of an insect and its manner of living there comes 

 naturally under this head. Information on the subject should be sought 

 for by careful personal observation, and to secure the best results each fact 

 as learnt should be noted down at the time, for future correlation and 



