254 Bird -Lore 



It is a long step, a very long step indeed, from the beautifully woven, sus- 

 pended nest of the common Oriole to the rocky ledge where the Murre lays 

 its single, long-pointed egg side by side with hundreds of similar individuals 

 of its kind. Nevertheless, the Oriole is no more constant in returning to the 

 accustomed nesting-site, and perhaps no more solicitous for the care of its 

 eggs and young, than the Murre. 



Think of the female Oriole, almost hidden with her eggs in a snug, deep 

 nest, swinging cosily with every breeze, safe from enemies and intruders as 

 well as from storms; and then try to picture hundreds and even thousands of 

 Murres clinging to a precarious position on a rocky islet, crowded closely side 

 by side, each parent holding its single egg, point outward, between its legs, 

 thus furnishing the warmth and protection which are necessary for proper 

 incubation. 



Or, look at the nest of a Spotted Sandpiper, if you are so lucky as to stum- 

 ble across one in the eel-grass along the sandy salt-water coast, or in the weeds 

 and low bushes along fresh water. It may appear to be nothing but a small 

 hollow, scooped in the sand, and lined with scarcely more than an occasional 

 spear of grass, or perhaps, merely with a few grasses pulled about and over it 

 as a screen; yet this nesting-site has been selected with much care and well 

 serves the purpose of hiding the large, spotted, cream-white eggs, as you will 

 be convinced when you have tried to find it a second time, or to direct 

 someone else to it. 



Remember that the young of the aquatic Murre and semi-aquatic Sand- 

 piper are praecocial — that is, hatched covered with down — ready to care for 

 themselves almost from the eggshell, while the altricial young of the Oriole are 

 blind, helpless, nearly naked creatures, unfit to seek for food or to find pro- 

 tection from the strong rays of the midday sun, from storms or chilling rains, 

 or to escape from enemies of their kind. 



The cradle of a bird, then, indicates to a considerable extent the habit of 

 the species to which it belongs, and the condition of the young at birth. 



As may be inferred, praecocial species have less use for elaborately con- 

 structed nests than altricial species, since they need to provide only a safe 

 receptacle for their eggs during the period of incubation, without concern for 

 a protective cradle for their newly hatched young. 



This explanation probably accounts in part for the simple means which 

 such birds have for safeguarding their eggs. 



Nests in holes or banks are of a higher type, and are intermediate between 

 the primitive devices of most of the praecocial birds and the complicated struc- 

 tures of some of the altricial birds. These nests in many cases, however, have 

 the inner part or lining carefully selected and arranged. Baron von Berlepsch, 

 in a long series of experiments with artificial nesting-holes, discovered how 

 symmetrical the inner dimensions of such cavities must be, before they are 

 suitable, even with proper lining material, to serve as bird-cradles. 



