10 



THE ZOOLOGIST. 



surface of the sand. These impressions may be mistaken for 

 those of a bird, and have been attributed to worms. The Dunlin 

 runs over the sand looking for these marks, and also, as I 

 imagine, for disturbances of the sand made by the movements 

 of the crustaceans. When it decides on a likely place it probes 

 the sand rapidly in a certain direction until it comes on the 

 small animal. The same method is applied to Sandhoppers, 

 and the Dunlin is remarkably agile in leaping to secure the 

 crustacean if it jumps. When they are racing over the wet 

 sands during the ebb in search of univalves they are attentive 

 to the worm-casts, and can be seen now and then to plunge their 

 bills hurriedly into casts and to draw out small worms. The 

 extrusion of the casts is not continuous. It occurs periodically, 

 and, as the worms are very near to the surface at the time, 

 I believe the Dunlins overrun the sand on the look-out for 

 castings in the moment of extrusion, when they are able to 

 capture worms which may be out of reach at other times. The 

 same combination is used on areas showing no visible surface- 

 markings, and where the supply of food is limited. The Dunlins 

 probe for a while in one place, and look about for another place 

 to treat in the same way. So engaged they are most liable 

 to sight objects it may be a yard away, and to run swiftly to 

 secure them. This applies to several kinds of ground, and 

 includes the search for small bivalves in the sand. On muddy 

 areas crowded with open burrows, into which the inhabitants 

 have retired as far as they can go, the Dunlins run about 

 looking for what they can find. The worms are beyond reach, 

 but many of the Crustacea have the terminal portions of their 

 burrows recurved ; in some cases the blind ends are within a 

 quarter of an inch of the surface and close to the entrance. 

 The Dunlin inspects these burrows, and in some instances taps 

 gently round the entrance with an evident purpose, for it sud- 

 denly plunges the bill very obliquely into the mud and reaches 

 upwards with the point. Even then it may miss its object, and 

 the bill is seen to travel in a curved course towards the entrance 

 of the burrow as if following the crustacean, the capture of which 

 may be signalled at any moment by the snapping of the man- 

 dibles. For a long time I puzzled over these actions, repeated 

 so frequently, and it was not until I found mud plastic enough 



