213 
you will find a study that will give you hours of an intensely 
interesting occupation and leave you satisfied that you have 
gained recreation and information apart from business and 
business cares. 
All life is divided into two great kingdoms, the kingdom of 
animal life and the kingdom of plant life. We readily recog- 
nize the members of these two kingdoms and will avoid defini- 
tions. I want to call your attention to the inter-relations and 
the inter-dependence of these divisions of life for it is not the 
insects but their relation to plant life, that forces our attention 
to the subject. 
If it were possible for all the offsprings of a certain species 
of animal to thrive, mature and in turn reproduce its kind and 
this could continue indefinitely, there would in time be abso- 
lutely no room on this earth for any other species. If all the 
seeds of any one kind of plant were to germinate, grow to a 
normal plant and develop seeds in turn and if this process 
could continue uninterruptedly, in time that plant would 
occupy the land to the exclusion of all other plants. This 
condition of affairs does not exist and a consideration of why 
a particular species of animal or kind of plant "does not pre- 
dominate to the exclusion of all others, gives us an insight 
into the inter-relations of plants and animals. 
The great struggle of all life is to live. After reproduction, 
the fundamental requirement is food. Indirectly all animal 
life is dependent for food on plant life. When the conditions 
are favorable for the growth of a certain plant, then, propor- 
tionally, as regards the fundamental requirement of food, the 
conditions are favorable for the increase and development of 
the plant-feeding animals dependent upon that particular plant 
for food. The more abundant the food, the greater will be the 
increase of the feeders until the very numbers of the plant- 
feeding animals,, will, by their continued feeding, begin to 
decrease the numbers of the plant. The decrease in the num- 
bers of the plant might continue until there would not be 
sufficient food for the plant-feeding animals and this would 
bring about a decrease in the number of animals. This 
decrease in food might continue until the plant was exter- 
minated and this would threaten the extinction of the species 
of animals requiring that particular plant for food. In a state 
of nature, the problem is not as simple as stated and actual 
depletion of food, that is total destruction of plant life and 
consequent extinction of animal life, rarely occurs. The strug- 
gle is not wholly one of animals against plants but is com- 
plicated by many other factors, namely, the relations of ani- 
mals among themselves, the struggle of plants among them- 
selves, temperature, moisture, altitude, dryness, etc., so that, 
excesses in increase or destruction are not possible. In other 
words, there is maintained in nature between plants and ani- 
