506 IX. CAROTENOIDS AND VITAMINS A 



resembling violaxanthin and taraxanthin, but distinct in properties from 

 either of these ; it was named canaryxanthophyll. Lutein was found to be a 

 second carotenoid widely distributed in feathers. According to Brock- 

 mann and Volker/^ the following classification of feather carotenoids en- 

 compasses the various types : 



{1) Contains mostly lutein and little canaryxanthophyll. 



(2) Contains only a little lutein. 



(3) Contains considerable canaryxanthophyll. 



Although Brockmann and Volker^^ noted that the canary could store lu- 

 tein in the fat, in the liver, and in the egg yolk, it changed the carotenoid 

 into a new taraxan thin-like xanthophyll before it was secreted into the new 

 yellow feathers. In addition to the above three groups, two other pig- 

 ments are occasionally found, namely a green one in the gray -headed wood- 

 pecker (Picus canus), and the green woodpecker, yaffle, or rain -bird (P. 

 viridis), and a red pigment in the fire-finch or weaver (Pyromelana francis- 

 cana) . 



Test*^- noted the presence of three pigments in the feathers of the yellow- 

 shafted woodpecker or Northern flicker {Colaptus auratus luteus), i.e., (a) 

 a taraxanthin-like substance, (6) an unidentified red neutral carotenoid, 

 suggesting astacene, occurring both in the free form and as an ester, and 

 (c) a-carotene. Although a-carotene comprises a minor part of the color in 

 C. auratus luteus, in the West Indian gilded woodpecker (C. chrysocaulosis) , 

 and in the southwestern gilded woodpecker (C. chrysoides), it plays a 

 major role in the closely related red-shafted flicker (C. cafer collaris). 



Kritzler^^^'^^^ identified three carotenoid pigments in the plumage of the 

 African bishop birds, the wild-fire weaver (Eupledes franciscanus) , the 

 grenadier weaver (Euplectes orix or Pyromelana oryx), and the black-bel- 

 lied weaver {E. nigroventris) , and in the head plumes of the red-headed 

 woodpecker (Melanerpes erythrocephalus) . These are characterized ac- 

 cording to their adsorption on alumina as Ri, lutein, and R2. Carotenoids 

 of unkno^\^l composition have been found in the yellow and red wings of a 

 number of parrots.*^^-^^^ These include the Australian grass parrakeet or 

 budgerigar (Melopsittacus undidatus Shaw), the Roselle parrakeet (Platy- 

 cercus eximius), the red lory {Eos cyanogenys), the red and black lory 



582 F. H. Test, Univ. Calif. Pub. Zool, 46, 371-389 (1942). 



583 H. Kritzler, Physiol. Zool, 16, 241-255 (1943). 

 58^ H. Kritzler, Anat. Record, 84, 528-529 (1942). 



585 O. Volker, Biol. Zentr., 62, 7-13 (1942). 



586 O. Volker, /. /. Ornithol, 84, 618-630 (1936); 85, 136-146 (1937); 87, 639-643 

 (1939). 



