1 1 8 Unconscious Memory 



correct diagnosis of their malady with a therapeutical 

 knowledge which they cannot possibly have acquired. 

 Dogs will often eat a great quantity of grass — particularly 

 couch-grass — when they are unwell, especially after spring, 

 if they have worms, which thus pass from them entangled 

 in the grass, or if they want to get fragments of bone 

 from out of their stomachs. As a purgative they make use 

 of plants that sting. Hens and pigeons pick lime from 

 walls and pavements if their food does not afford them 

 lime enough to make their eggshells with. Little children 

 eat chalk when suffering from acidity of the stomach, 

 and pieces of charcoal if they are troubled with flatulence. 

 We may observe these same instincts for certain kinds 

 of food or drugs even among grown-up people, under 

 circumstances in which their unconscious nature has un- 

 usual power ; as, for example, among women when they 

 are pregnant, whose capricious appetites are probably 

 due to some special condition of the foetus, which renders 

 a certain state of the blood desirable. Field-mice bite 

 off the germs of the corn which they collect together, 

 in order to prevent its growing during the winter. Some 

 days before the beginning of cold weather the squirrel is 

 most assiduous in augmenting its store, and then closes 

 its dwelling. Birds of passage betake themselves to 

 warmer countries at times when there is still no scarcity 

 of food for them here, and when the temperature is con- 

 siderably warmer than it will be when they return to us. 

 The same holds good of the time when animals begin to 

 prepare their winter quarters, which beetles constantly 

 do during the very hottest days of autumn. When swallows 

 and storks find their way back to their native places over 

 distances of hundreds of miles, and though the aspect of 

 the country is reversed, we say that this is due to the 

 acuteness of their perception of locality ; but the saiue 

 cannot be said of dogs, which, though they have been 

 carried in a bag from one place to another that they do" 

 not know, and have been turned round and round twenty 



