THE CRUDEST NEST FORMS 71 



its discovery more difBcult, as is conclusively shown 

 by the numbers that escape detection even when built 

 in the most frequented or exposed situations. Some 

 of the Tyrant Birds make very crude nests. Thus, 

 Tyrannus dominicensis is described by Dr Christy as 

 astonishingly small flat structures of just a few twigs 

 placed crossways on each other, and placed at the 

 extremity of a horizontal branch from six to ten feet 

 above the ground. 



Having now dealt with the crudest nest-forms that 

 are built away from the ground in trees and other 

 vegetation, we will proceed to examine the leading 

 types of such structures that are placed upon or in 

 the earth. Of these some of the crudest nest-builders 

 are the Sand-Grouse comprising the order Pediophili. 

 In fact we might almost class these birds as nestless 

 species, as the only provision that they make for 

 their eggs consists of a mere hollow scraped in the 

 soil, round the margin of which a few blades of 

 withered grass or bits of dry weed are carelessly 

 arranged ; but even this latter finishing touch is 

 frequently omitted. As in the case of the Ostrich 

 and not a few other birds that breed on deserts and 

 sands, the eggs are left during the heat of the day, 

 the sun furnishing sufficient warmth for the purpose 

 of incubation. Incidentally we may mention that 

 Sand-Grouse are specially interesting to the British 

 naturalist, not only because these birds have visited 

 our islands, sometimes in enormous numbers, as 



