CAHOWS AND LONGTAILS 



written, an outer shelf above the arch fell and 

 killed a tropicbird. A few days later I dug out the 

 bird and found a downy nestling which had died of 

 starvation in an inner hollow. This was the first 

 tragedy of the arch ; an infinitesimal inorganic cli- 

 max bringing to a close one of the topmost twigs 

 of the tree of organic evolution.) 



Even more than hummingbirds, tropicbirds are 

 beings of the air. Infinitely more than the birds of 

 paradise do they deserve the name apodus, for 

 neither legs nor feet are clearly to be seen and are 

 used as little as possible. 



In flight two small patches are visible flattened 

 below against the base of the tail — the webbed toes 

 tucked out of the way. They are hardly more in 

 evidence when the owner alights on the water or 

 when it enters its nest. Like the landing of an over- 

 weighted airplane, the entering of the nesting hole 

 by a tropicbird is a serious affair. Three or four 

 false attempts are usually made, before the trajec- 

 tory and speed are adjusted to the wind, and the 

 parti-colored chassis is deposited on a slight ledge 

 or actually in the hole. The bird then wriggles and 

 pushes forward, seal-like, until it disappears. 



One of the most useless characters I can imagine 

 is the long, attenuated central pair of tail feathers. 

 It surely can be of no courtship value, for these 

 birds court and mate in mid-air, almost always two 

 males in fierce rivalry. Under these circumstances 

 it is difficult to imagine any nice adjustment as to 

 admired length, resiliency or sweep of the feathery 



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