Ftirther Observations on Young Birds. 99 



record the details of my own work will be fulfilled. There 

 are many activities and modes of behaviour which are 

 generally assumed to be instinctive and due to heredity, 

 but which may be the result of tradition, handed on by 

 example from parents to offspring. Partridges, for 

 example, when they jug, nestling close together at night, 

 would seem, from the appearance of the droppings, which 

 are generally deposited in a circle of only a few inches in 

 diameter, to arrange themselves in a circle, tails inwards 

 and heads outwards. Is this behaviour instinctive or is 

 it traditional ? The young of the colin (Ortyx virginiana), 

 we are told,* "when the shades of evening approached, 

 crowded together in a circle on the ground, and prepared 

 themselves for the slumbers of the night by placing their 

 tails all together, with their pretty mottled chins facing to 

 the front in a watchful round-robin." The fact that these 

 birds behave thus, apparently instinctively, would lead one 

 to surmise that the behaviour is instinctive in the partridge. 

 My own birds died at too early an age for this point to be 

 determined. 



We may now summarize some of the general conclusions 

 to be drawn from our observations as follows : — 



1. That which is congenitally definite as instinctive 

 behaviour is essentially a motor response or train of motor 

 responses. Mr. Herbert Spencer's description of instinct 

 as compound reflex action is thus justified. 



2. These often show very accurate and nicely adjusted 

 congenital or hereditary co-ordinations. 



3. They are evoked by stimuli, the general type of 

 which is fairly definite, and may, in some cases, be in 

 response to particular objects. Of the latter possibility we 

 have, however, but little satisfactory evidence. 



4. There does not seem to be any convincing evidence 



* Yarrell, "British Birds," sub. spec. 



