INSECT LIFE IN INDIA AND HOW TO STUDY IT. 1G5 



given a prominent place in this re-arrangement, and old well-known 

 friends relegated to the background as of comparatively small signifi- 

 cance. I will not say that much can be accomplished upon these lines at 

 present, but I trust to be able to aid the student to some extent in this 

 direction. 



Insect Life in the field or orchard, as elsewhere, may be divided 

 into two great groups, in the first of which come the Insects actually 

 injurious to plant growth and which are in consequence inimical to 

 man ; in the second the predacious and parasitic Insects, which from 

 their habits of preying upon their fellows may be considered as the 

 friends of the human race. It should be noted that these latter are 

 in their turn devoured by other Insects ; whilst fungi undoubtedly 

 lend their help in keeping within bounds the enormous increase in 

 numbers which would otherwise, and at times does, take place owing 

 to the great fertility and prolificness of Insect Life. 



In fact study and observation show that in all probability no Insect 

 exists upon the face of the earth which has not enemies of one kind or 

 another to contend with, which aid in keeping down its numbers. 

 That this is as it should be becomes evident when it is remembered that 

 Huxley calculated that the produce of a single Aphis (the green blight 

 found on rose bushes, &c, are Aphids) would, in the course of ten 

 generations, supposing all the individuals to survive, ' contain more 

 ponderable substance than 500 millions of stout men, that is, more 

 than the whole population of China.' The increase of this one family 

 of insects is such that, were they not kept under, it has been calculated 

 that in the course of two or three years they would, deriving their 

 nutriment as they do directly from the plant in the growing state, 

 leave no plant food available for other animals save that which might be 

 derived from plants they did not attack. In other words, man would 

 be very soon cleared off the face of the earth had not nature provided 

 checks against undue increase of its Insect population. At times the 

 preyed-upon obtain for a season the upper hand, and the alarming 

 rate at which they then -spread is known to all. 



In conclusion, I may say that in these papers I do not propose to 

 make use of more technical terms than are absolutely essential, whose 

 explanation is to be found in any elementary text-book on Entomology. 

 Explanations will be given in all cases where it is considered necessary. 

 To the readers of this Journal no further apology is necessary for such 

 technicalities as are unavoidable. 



