FEA THERS 



241 



" contour feathers " (pennx or plumai), " downs " {plumule), " half- 

 downs " (semiplumai) and "hairlike feathers" (filophmiai), hnt numer- 

 ous intermediate stages connect these principal forms ; and there 

 must also be added as a special feature the nestling feathers. 



The " Contour-feathers," as their name implies, are those Avhich 

 apjjear on the sui'face of the bird. As a rule they have a com- 



Perspective View of a portion of two adjacent Barbs (B, B) looking from the Shaft 



towards the edge of the feather. 

 hd, distal barbules ; hp, proximal barbules. 



Oblique Section through the Proximal Barbules in a plane parallel to the Distal 



Barbules of the last Figure. 



Letters as before ; 1, 2, 3, Baibicels and hamuli of the ventral side of the distal barbule ; 



4, Barbicels of the dorsal side of the same, without hamuli. 



From The This, 188T, plate xii. 



paratively strong shaft, Avith lioth inner and outer Avebs complete, 

 and they attain their fullest development as rectrices and remiges. 

 Many Contour-feathers, especially those which are ornamental, have 

 no cilia, and therefore no hamuli, while occasionally the radii are 

 rare, so that their webs are disconnected and have a more or less 

 "fluffy" appearance, such as is shcAvn by the pectoral tufts of the 

 Birds-of-Paradise, the dorsal plumes of the Egrets, and the crest 

 of the Peacocks and Crowned Cranes. The cilia of " metallic " 



16 



