1 8 Oberholser Description of a JVew Vireo. 



green in contrast to the head and nape; the much more yellowish flanks 

 and sides; the rather less purely white under surface; and the decidedly 

 shorter tail. 



Specimens to the westward in the range of Vireo bellii medius indicate 

 intergradation with pusillus, and taken in connection with hardly typi 

 cal examples of the latter from extreme western Texas, show pretty con 

 clusively that to pusillus there belongs a trimomial name. 



Average millimeter measurements of five specimens of each of these 

 three forms are as follows: 



Vireo bellii bellii (Kansas and Illinois): wing, 55.6; tail, 45.8; exposed 

 culmen, 10; tarsus, 18.5; middle toe, 9.8. 



Vireo bellii medius (Texas): wing, 54.1; tail, 46.3; exposed culmen, 9.7; 

 tarsus, 18.5; middle toe, 9.4. 



Vireo bellii pusillus (California): wing, 54.6; tail, 49.6; exposed culmen, 

 9.3; tarsus, 18.9; middle toe, 9.9. 



