BIRBS OF NOKTH AND MIDDLE AMERICA. 5 



straight {C. viridis) or more or less strongly sinuated, the posterior 

 convexity (beneath nostril) more decided than the anterior concavity; 

 mandibular tomium nearly straight. Nostril exposed, small, roundish. 

 Rictal bristles not obvious. Wing rather long (more than three and 

 a half to about four and three-fourths times as long as tarsus), pointed 

 (ninth to sixth primaries longest and nearly equal, ninth decidedly 

 shorter than sixth only in 0. pretrii); primaries exceeding secondaries 

 by about length of tarsus or a little more. Tarsus longer than middle 

 toe with claw; lateral claws reaching about to base of middle claw; 

 hind claw decidedly shorter than the digit. 



Coloration. — Chiefly or largely uniform bright grass green, with 

 more or less of yellow on under parts, the upper parts often partly blue. 



Range. — ^Tropical America (except West Indies), from southern 

 Mexico to southern Brazil and Bolivia. 



There is considerable variation in details of form among the differ- 

 ent species of this genus. The type, 0. viridis, has the bill far more 

 slender than any of the others, with the culmen and gonys less 

 strongly curved, the maxillary tomium nearly straight and very indis- 

 tinctly notched subterminally; the tip of the maxilla scarcely decurved 

 or uncinate, and the mandibular tomium slightly concave anteriorly, 

 the tip of the mandible being thus obviously recurved and acuminate. 

 The tarsus is also relatively shorter, and the upper parts are mainly 

 blue. C. occipitalis represents the opposite extreme in shape of bill, 

 all the other species being much nearer to it, however, than to C. viri- 

 dis. All have the four outermost primaries nearly equal and longest, 

 except C. pretrii, which has the ninth much shorter than the sixth, 

 the eighth being longest. The last-named species is unique in having 

 a yellow patch on the rump. 



KEY TO THE SPECIES OP CHLOROPHONIA. 



a. A patch of blue on occiput and hinder part of crown. 

 6. Breast bright yellow, margined anteriorly by a semicircular narrow band or 

 collar of blackish or dark brown. (Adult males. ) 

 ' ti. Forehead and superciliary region green; occipital spot smaller, turquoise blue; 

 hindneck green. (Southern Mexico; Guatemala.) 



Chlorophouia occipitalis, adult male (p- 6) 



cc. Forehead and superciliary region yellow; occipital spot large, campanula 



blue; hindneck cerulean or turquoise blue. (Costa Rica; Veragua; Chiri- 



qui. ) Chloraphonia callophrys, adult male (p. 7) 



bb. Breast green, not margined anteriorly by blackish or dark-brown collar. 

 (Adult females. ) 

 c. Occipital spot smaller, turquoise blue; hindneck entirely green, without dis- 

 tinct, if any, blue collar across lower part. 



CMorophonia occipitalis, adult female (p. 6) 

 cc. Occipital spot larger, campanula blue; hindneck mostly blue, with distinct 

 collar of turquoise blue across lower portion. 



Chlorophonia callophrys, adult female (p. 7) 

 aa. No blue on pileum, or else this merely indicated. (Immature males and females 

 and young. ) 



