Vol 'i9i9 XYI ] Wetmore, The Palate in Icteridce. 193 



Scattered among the leaves were many acorn shells, most of which 

 had been cut in two in a line transverse to the longitudinal axis. 

 Some had fairly smooth, clean-cut margins, while others were 

 roughened and jagged. In searching through the leaves I picked 

 up one acorn still intact that had been dropped by one of the birds, 

 perhaps when the flock was frightened up, in which a line had been 

 impressed entirely around the center. In this the impressions of 

 the palatal keel were distinctly visible. 



When attention was once attracted to this manner of feeding 

 other incidents were noted in which the palatal keel was brought 

 in play. On one occasion on the streets of Washington a Purple 

 Grackle was observed attempting to split open a kernel of corn 

 dropped from some passing dray. The bird held this grain in the 

 slight notch near the center of the bill and pressed it against the 

 angular keel. The grain proved refractory, as it snapped out sev- 

 eral times, dropping 8 or 10 inches away, to be seized and again 

 compressed. Watching until it had been dropped I frightened 

 the bird and secured the kernel of corn. On one side four grooves 

 impressed in the hard outer surface were visible showing where, 

 and with what force, the sharp keel had been applied. 



Apparently the palatal ridge develops with the gradual growth 

 of the bill, and becomes fully functional shortly after the immature 

 bird is left by its parents to its own resources in securing food. 

 It seems to be fully grown in all by the middle of September. In 

 many adult specimens the ridge shows signs of heavy wear from 

 the nearly constant use to which it is put. In some the cutting 

 angle was well rounded in front from constant abrasion, while in 

 others the anterior margin had become irregular and broken. In 

 one specimen the thin lower margin of the compressed keel was 

 entirely worn away, leaving a low rounded projection in which the 

 two sides of the fold by which the keel had been formed were 

 clearly visible, with a line of separation between them. It was 

 interesting to note that the palatal ridge was usually well worn 

 in old adults, taken in late fall or early spring, belonging to the 

 northern races (Quiscalus q. quiscula and Q. q. ceneas) while little 

 or no wear was apparent in similar specimens of the southern form 

 (Q. q. aglxEus) from South Carolina and Florida. The data avail- 

 able from the examination of a small number of stomachs of this 



