84 GRALLvE. 



gravel naturally along with their food, can be maintained and 

 continue equally fat upon half the quantity of grain. 



The British birds that come nearest to what may be con- 

 sidered as the commencement of this order, are the lowland 

 gallinse and the runners ; but though these feed much on the 

 surface, they also feed higher up than is the general habit of 

 the grallse. Those pick seeds from the tops of high plants, 

 and eat the leaves and tops of some green vegetables, which 

 the birds of the present order very rare]y do. The habits of 

 the bustards approach the nearest to those of the grallse ; 

 but then the bustards are so exclusively birds of dry pas- 

 tures, that it is a contradiction in terms to class them as 

 grallidse, or birds like waders, and much more so to class 

 them as gralla, or actual waders. 



The bodies of all the order are poised with the direction of 

 the centre of gravity so much within the base formed by the 

 feet, that they have great power over the neck, and can 

 thus command a large portion of space with the point of the 

 bill, while the axis of the body remains in nearly the same 

 position ; and, especially in those species that fish, the extent 

 and rapidity of motion to the bill, by means of the extension 

 and flexure of the neck, are very remarkable. Their legs are 

 also more developed than those of birds that feed even occa- 

 sionally on the wing or the perch. The tarsi are long and 

 in general clean and light in their structure, as is the case 

 with most animals which use their feet only for swift pro- 

 gressive motion, and not for clutching or hopping. The 

 femur or thigh-bone is more free ; the articulation of the 

 tibia with the tarsus more firm ; and the whole leg comes 

 more into action than that of other birds, the running birds 

 only excepted. They are thus enabled to take longer steps 

 with the same muscular exertion ; and they get over the 

 ground fast and with little fatigue. When they fly, they 

 extend the legs backwards, and at the same time stretch the 



