9 8 BIRDS OF LA PLATA 



reacted on and modified the habits. In seeking for 

 and taking food, the body is required to perform 

 certain definite motions and assume repeatedly the 

 same attitudes ; this is most frequently the case in 

 birds of aquatic habits, A readiness for assuming at 

 all times, and an involuntary falling into, these 

 peculiar attitudes and gestures appears to become 

 hereditary ; and the species in which they are the 

 most noticeable seem incapable of throwing the habit 

 or manner off, even when placed in situations where 

 it is useless or even detrimental, T rings rapidly 

 peck and probe the mud as they advance ; Plovers 

 peck and run, peck and run again. Now I have 

 noticed scores of times that these birds cannot possibly 

 lay aside this habit of pecking as they advance ; for 

 even a wounded Plover running from his pursuer 

 over dry barren ground goes through the form of 

 eating by pausing for a moment every yard or so, 

 pecking the ground, then running on again. 



The Paraguay Snipe, and probably other true 

 Snipes, possesses the singular habit of striking its 

 beak on the ground when taking flight. In this 

 instance has not the probing motion, performed 

 instinctively as the bird moves, been utilised to assist 

 it in rising 4 



Grebes on land walk erect like Penguins and have 

 a slow, awkward gait ; and whenever they wish to 

 accelerate their progress they throw themselves for- 

 ward on the breast and strike out the feet as in 

 swimming. 



The Glossy Ibis feeds in shallow water, thrusting 



