394 VIREOS 



FAMILY VIREONIDiE: VIREOS. 



GENUS VIREO. 



General Characters. — Bill similar to that of the shrikes, distinctly 

 hooked and notched at tip ; rictal bristles conspicuous ; wings equal to or 

 longer than tail ; tail nearlj^ even ; claws stout, strongly curved ; side toes 

 unequal in leng-th. 



KEY TO ADULTS. 



1. Head strikingly marked. 



2. Lores and orbital ring white in sharp contrast to gray or black of 

 head. 



3. Top and sides of head black, atricapillus, p. 391 



Fig. 485. 

 3'. Top and sides of head gray. 



4. Back gray. Southern Rocky Mountain region. 



plumbeus, p. 397. 

 4'. Back olive green. 



5, Brig'hter olive green. Eastern United States. 



solitarius, p. 89(1 



5'. Duller olive green. Western United States. 

 cassinii. p. 39(5 . 



2'. Lores and orbital ring not white in sharp contrast to 

 head. 



3. Sides and flanks tinged with olive gray. 



olivaceus, p. 395. 



FiR. 4S(;, 



Fig. 487 



8'. Sides and flanks bright olive yellow . . . flavoviridis, p. 395. 

 1 . Head not strikingly marked. 



2. Upper parts gray. Western Texas to southern California. 



viciiiior, p. 400. 

 2'. Upper parts bright olive green or tinged with olive. 

 3. Upper parts bright olive green. 



4. Larger and brighter noveboracensis. p. 398. 



4'.Smaller and duller. Rio Grande Valley . . micrus. p. 399. 

 3'. Upper parts tinged with olive green. .— seS^S^^ 



4'. Wings marked with white. Fig. 488. 



5. Wing about 2.18. 



6. Wing with two distinct bands. Mississippi Valley and Plains. 



bellii, p. 399. 

 6'. Wing- usually with only one band. Arizona and California. 



pusillus, p. 400. 

 5'. Wing- about 2.50. 

 C). Wing bars white. 



