98 Unconscious Memory 



out ai.y co-operation on its own part. In warm climates 

 many birds only sit by night, and small exotic birds that 

 have built in aviaries kept at a high temperature sit little 

 upon their eggs or not at all. How inconceivable is the sup- 

 position of a mechanism that impels the bird to sit as soon as 

 the temperature falls below a certain height ! How clear 

 and simple, on the other hand, is the view that there is an 

 unconscious purpose constraining the volition of the bird 

 to the use of the fitting means, of which process, however, 

 only the last link, that is to say, the will immediately 

 preceding the action falls within the consciousness of the 

 bird! 



In South Africa the sparrow surrounds her nest with 

 thorns as a defence against apes and serpents. The eggs 

 of the cuckoo, as regards size, colour, and marking, in- 

 variably resemble those of the birds in whose nests she 

 lays. Sylvia rufa, for example, lays a white egg with 

 violet spots ; Sylvia hippolais, a red one with black spots ; 

 Regulus ignicapellus, a cloudy red ; but the cuckoo's egg 

 is in each case so deceptive an imitation of its model, that 

 it can hardly be distinguished except by the structure of 

 its shell. 



Huber contrived that his bees should be unable to 

 build in their usual instincti\'e manner, beginning from 

 above and working downwards ; on this they began build- 

 ing from below, and again horizontally. The outermost 

 cells that spring from the top of the hive or abut against 

 its sides are not hexagonal, but pentagonal, so as to gain 

 in strength, being attached with one base instead of two 

 sides. In autumn bees lengthen their existing honey cells 

 if these are insufficient, but in the ensuing spring they 

 again shorten them in order to get greater roadway between 

 the combs. When the full combs have become too heavy, 

 they strengthen the walls of the uppermost or bearing 

 cells by thickening them with wax and propolis. If larvae 

 of working bees are introduced into the cells set apart for 

 drones, the working bees will cover these cells with the 



