1 62 Instijict. 



Although there is much connected with this 

 subject that we cannot understand, there are cer- 

 tain facts, such as we have referred to, plain to ev- 

 ery observer, showing a wonderful correlation of 

 instinctive action between the parent and its young. 



This correlation commences immediately on the 

 hatching of the young bird, and it is common to 

 thousands of kinds of birds, under a variety of con- 

 ditions. 



Many illustrations of the same principle can be 

 found among the invertebrate animals ; and with 

 some of them, this principle of correlation of In- 

 stinct is of wider application, — a third element often 

 comes in to act, as will appear in considering the 

 following topics : 



1. Instinct of anunals requiring certain changes 

 in other kinds of animals^ or in plants^ for the com- 

 pletion of its work. 



2. The peculiar instijict of one stage of being as 

 preparatory to another^ in which that instinct is en- 

 tirely lost ; as in the case of many insects. 



Every plant has certain relations to the inorgan- 

 ic world, as we have pointed out in a previous lec- 

 ture. There is a correlation of its changes and 

 developments, both as to time and conditions re- 

 quired for them, with the changes in the inor- 

 ganic world. 



The animal kingdom, as a whole, not only de- 

 pends upon the vegetable, but it is fitted to the vege- 

 table kingdom, in many respects, as that is related 

 to the inorganic world. Important physiological 

 changes in animals, as well as change of instinct, or 



