100 BIRDS-NESTING. 



already been alluded to in the case of Traill's fly- 

 catcher (pages 26-29) , but another instance may not 

 be out of place, as showing how such variations may 

 exist and long remain undiscovered. 



There is no bird perhaps, whose nest has seemed 

 more uniform in its adherence to the accepted type 

 of structure in every respect, than the orchard oriole 

 (Icterus spurius) . It covers a wide extent of terri- 

 tory in its habitat, ranging from the Connecticut river 

 to the Rocky mountains and from Lake Superior to 

 Texas. The ordinary style of its nest, which may 

 be accepted as typical, is that described so carefully 

 by Wilson, who unravelled from one of them a 

 single fibre of grass thirteen inches long, which had 

 been passed back and forth through the wall of the 

 nest no less than thirty-five times. Sometimes these 

 pensile nests, after the manner of the Baltimore 

 oriole's, are hung among the pendent tips of the 

 drooping branches of a willow or elm, several of 

 which may be woven into the sides and serve as up- 

 right ribs or stays. These nests are likely to be the 

 most deep and neatly made of any to be found. 

 But a favorite situation is in an apple or pear tree, 

 and here the nest is suspended by the brim, between 

 the prongs of a fork, like a vireo's and is more 

 cup-shaped and shallow. In both cases the walls are 

 rather thin (particularly in those made at the south, 



