1911] The Undescribed Juvenal Plumage of the Yucatan Jay. 155 



sooty black on inner web and rachis, (rachis white below) , outer 

 web bright blue like new back feathers. The blue on the tip of 

 the inner web gradually increases, from the outer feathers 

 inward, so that the inner secondary is uniform blue, with the 

 exception of the proximal portion of inner web. Under wing- 

 coverts sooty black, with faint lighter bars; tail bright blue 

 above, black below ; rachis black above and below ; thighs brown- 

 ish black, tinged with blue at the tarsal joint. Legs and feet 

 pale yellow ; bill orange yellow. Iris dark hazel brown. A small 

 patch of black feathers is appearing at either side of the breast 

 and scattered ones throughout the rest of the under parts, but 

 none on the head. In both this and the other individuals the 

 rectrices are so broken that it is impossible to state the amount 

 and place of occurrence of the white. Bill 32 mm., tarsus 46 mm. 



Sixteen Weeks Old (November 18, 1911). 



Feathers of the head, neck and upper breast deep black, a 

 few white feathers, interposed with black ones, remain above 

 and below the eyes and on the lores and chin. The lower breast 

 and abdomen are slightly tinged with blue, which becomes more 

 distinct on the under tail-covers. The back and scapulars are 

 uniform bright blue. The lesser coverts, carpal edge and inner 

 median coverts have been renewed and are like the back, but the 

 outer median coverts and all the greater coverts have not as yet 

 been moulted. Wing and unplucked tail feathers have not been 

 renewed, nor have the under wing-coverts and the feathers of 

 the thighs. The eye-lid is bright yellow, the bill and legs some- 

 what paler. The iris is dark slaty gray. All of the feathers, 

 except rectrices, remiges and upper wing-coverts, are loose in 

 texture, the barbs few, long and disconnected. Bill 33 mm., 

 tarsus 46.5 mm. 



Individual B. 



Seven Weeks Old. 



Similar to A, except that the sooty bases are present on 

 only a few isolated feathers ; a distinct blue tinge on the crown ; 

 thighs wholly bluish black; pectoral tracts of incoming black 



