OPEN NESTS 153 



varying size, and their nests are scattered thickly 

 over the chosen spot, sometimes a deep hollow filled 

 with muddy water marking the common spot where 

 the materials for the nests have been gathered. 



Next in order of sequence we have to consider the 

 open nests of the Cranes and various allied birds 

 associated under the term Gruiformes. Here again 

 we find not a little divergence in the character of the 

 nest to accommodate it to the peculiarities of the site. 

 Some of the nests, as we have already indicated, must 

 be classified as crude ; others, however, are massive 

 and elaborate, both types occurring in some cases in 

 the same species, according to the place on which 

 they rest. We may take as our typical Crane's nest 

 that of the Common Crane {Grus cijierea). Cranes 

 breed in scattered pairs in vast swamps and salt 

 marshes, and the size of the nest depends upon the 

 nature of the ground, the wetter the district the 

 larger the structure. The larger nests tower high 

 above the shallow water or swampy ground, and are 

 made of sedges, rushes, branches and twigs, and lined 

 with grass. The smaller ones, generally resting on 

 grass-clothed mud, are low flat structures of beaten 

 down herbage — mats several inches in thickness and 

 about eighteen inches across. The smallest nests of 

 all are those situated on the dry hummocks, and are 

 little more than trampled hollows lined with pieces of 

 dead vegetation. Then the nest of the Demoiselle 

 Crane (G. virgo) is described as being a very slight 



