HERODIONES. 215 



consist of a score species, and are nearly as cosmopolitan as the 

 Ardeida. 



Of the 15 Japanese species belonging to the suborder Herodiones, 

 1 only is peculiar to Japan during the breeding-season ; 3 breed in the 

 Eastern Palsearctic Region; 5 breed both in the Palsearctic and 

 Oriental Regions, one of which breeds also in the Nearctic Region ; 

 whilst 6 may be regarded as exclusively tropical, breeding in the 

 Oriental Region. 



Genus Ardea. — The typical Herons differ from the Night-Herons 

 {Nycticorax) and agree with the Bitterns {Botaurus) in having the 

 whole of the front of the tarsus covered with wide transverse plates ; 

 but they agree with Nycticorax and differ from Botaurus in having 

 twelve tail-feathers, and in having the inner toe shorter than the 

 outer. They differ from both these genera in having the tibia bare 

 of feathers for a greater distance than the length of the hind toe 

 without the claw, but this character is subject to much individual 

 variation. In Ardea garzetta it varies from 1*5 to 2*5 inches, being 

 sometimes longer and sometimes shorter than the length of the inner 

 toe without the claw. In Ardea coromanda it is always shorter than 

 the inner toe, but never so short as the hind toe without the claw. 



The genus Ardea may be divided into few or many subgenera 

 according to the caprice of the systematist. The Japanese species 

 consist of one typical Heron, five Egrets, and a Reef-Heron ; but I 

 know of no generic characters to distinguish one group from another. 



201. ARDEA CINEREA. 

 (HERON.) 



Ardea dnerea, Linneiis, Syst. Nat. i. p. 23G (176G). 



The Common Heron is a large grey-backed species like the Purple 

 Heron (which is very likely to occur in Japan), but may be distin- 

 guished from it at all ages by the colour of its forehead and crown, 

 which is slate-grey in young in first plumage, moulting to white in 

 the adult, whilst that of the Purple Heron is russet-brown in the 

 young, moulting to black in the adult. 



Figures : Dresser, Birds of Europe, iv. pi. 395. 



The Common Heron is somewhat sparingly distributed in all the 

 Japanese Islands. There is an example in the Swiuhoe collection 



