Genus— I XOBRYCHUS. 
IxoBRYCHUS Billberg, Synops. Faunaa Scand., Vol. I., p. 166, 
1828 (c/. Austral Av. Eec., Vol. 11., p. 41, 1913) 
Ardeola (not Boie 1822) Bonaparte, Ann. Lye. Nat. 
Hist. New York, Vol. II., p. 307, 1826 
Ardetta Gray, App. List Genera Birds, p. 13, 1842 
Erodiscus Gloger, Hand. u. Hilfsb. Naturg., p. 410, 1842 . . 
Type I. minutus. 
Type 7. exilis. 
Type I. minutus. 
Type I. minutus. 
Smallest Ardeine birds with comparatively long biUs, medium necks, long 
wings, short tail, and short legs with long toes. 
The head is crested, but neither dorsal ornamental feathers nor breast- 
ornaments are developed. 
The culmen is long, slender, and serrated on the edges of the mandibles, 
an indistinct notch being present ; the culmen is longer than the tarsus and 
about one-third the length of the wing. 
The wing is long, with the first primary longest. 
The tail is short and even, and co7nposed of ten feathers. 
The legs are short with practically no exposed tibia present ; the meta- 
tarsus is regularly scutellate in front and reticulate behind, and is shorter 
than the culmen and about equal to the tail. The toes are comparatively 
long with the interwebbing obsolete, and the middle toe is shorter than 
the metatarsus. 
This generic form was first differentiated by Bonaparte who used for it 
the name Ardeola, but that name had been previously introduced by Boie 
for a species which is now considered generically distinct. 
This error was corrected by Gray, in 1842, who substituted Ardetta, by 
which name the genus has been recently called. The same year, Gloger 
introduced Erodiscus, but fortunately there is no occasion to investigate 
the priority of these two names as in 1828 Billberg had used for the Bitterns 
the generic name Ixobrychus. In 1907 the type of this was named by Stone 
as A. 7 ninuta Linne, so that Ixobrychus was made available for this group. 
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