380 ARDEIDJ3. 



I'. Nude tibia slightly longer than inner toe 

 and claw or shorter ; plumage either dark 

 grey throughout, except on throat, or 

 pure white throughout ; culmen not 

 exceeding or just exceeding tarsus in 



length LEPTERODIUS, p. 390. 



c'. Nude tibia shorter than inner toe and claw. 

 c". Wings, body, and tail white. 



a 3 . Head and back white in winter, 

 ochreous buff in breeding-season ; 



culmeu shorter than tarsus BUBULCUS, p. 388. 



b 3 . Head and back always coloured, not 

 buff, or only in parts buff ; culinen 



longer than tarsus ARDEOLA, p. 392. 



d" . Wings, body, and tail not white. 



c 3 . Culmen longer than tarsus BUTORIDES, p. 394. 



d 3 . Culrnen about equal to tarsus; bill 



deep at base NYCTICORAX, p. 396. 



e 3 . Culmen shorter than tarsus GORSACHIUS, p. 398. 



.b. Tail-feathers 10. 



d'. Middle toe and claw not longer than 

 culmen. 



e". Size small, wing under 6 inches AEDETTA, p. 399. 



f. Size larger, wing over 6 inches DUPETOR, p. 403. 



e'. Middle toe and claw longer than tarsus, 



which is much longer than bill BOTAUBUS, p. 405. 



Genus ARDEA, Linn., 1766. 



Bill long, compressed, pointed ; culmen nearly straight ; both 

 mandibles slightly serrated at commissure, upper mandible grooved 

 on each side of culmen ; nostrils subbasal, elongate, situated in the 

 groove. Sides of head to behind the eyes naked. Tarsus long, 

 scutellate in front ; tibia half-naked. Wings ample ; tail short. 

 Upper surface grey ; the feathers at the base of the neck and the 

 scapulars elongate, forming ornamental plumes ; no dorsal train. 

 Head crested. 



This genus is almost cosmopolitan ; of the ten species known 

 half occur in India. The Purple Herons, which have a pro- 

 portionally larger foot and differ slightly in habits, are placed by 

 Sharpe in a distinct genus, Phoyx, but the division, though justi- 

 fiable, appears scarcely necessary. 



Key to the Species. 



a. Mid-toe and claw as long as tarsus or longer ; 



crown and crest black A. manillensis, p. 381. 



b. Mid-toe and claw shorter than tarsus. 



a'. Crown of head white (grey in young), 



crest black A. cinerea, p. 382. 



b'. Crown and crest grey. 



a". Lower parts grey A. sumatrana, p. 383. 



b". Lower parts white A. insignia, p. 383. 



c'. Crown and crest chestnut A. goliath, p. 384. 



