66 BIRDS' NESTS 



his breast-bone on the ground and kicks the sand 

 behind. When one side is sufficiently deep he turns 

 round and repeats the same operation, until a round 

 hole about three feet in diameter and one foot deep 

 is formed. According to this writer the eggs are 

 covered with sand to protect them from the fierce 

 rays of the sun, but there can be no doubt that many 

 eggs are incubated in part by solar warmth. It has 

 been frequently stated that the male bird alone in 

 this group (Ratit^) incubates the eggs, but this is 

 denied by Mr Crawston, who asserts that the male 

 and female ostrich share the labour, the male sitting 

 during the evening and night. It should be remarked, 

 however, that equally trustworthy observers maintain 

 that incubation is performed by the males alone. 

 Then again the Tinamous (Crypturi), a Neotropical 

 group, are very crude nest-builders, their procreant 

 cradle consisting of a mere hollow scraped in the 

 ground, in which a few feathers are strewn as likely 

 as not by accident rather than by design. Many of 

 the Falcons must also be classed as builders of the 

 crudest forms of nest. The Jer Falcon (in its seve- 

 ral representative or geographical forms), the most 

 typical of the group, prepares no more than a mere 

 hollow on the ledges of the cliffs in which to deposit 

 her eggs. The Peregrine is equally unsolicitous; in 

 fact, all the world over the typical Falcons are satis- 

 fied with the crudest provision for their eggs. Some 

 of the smaller species, however, either annex the 



