ARDEID.E: HERONS. 871 



Balceniceps rex, the extraordiuary Shoe-bill or Whale-head of Africa, with euorinous head 

 aud bill, thick ueck, and one pair of powder-down tracts, is type of a family Bulccnicitipidcey 

 which may belong here; but it approaches Storks, aud its peculiarities are so great that it may 

 constitute a separate superfiimily group. The Boat-bill of Central America, with a singular 

 shape of bill that has suggested the name, and 4 pairs of powder-down tracts, constitutes an- 

 other family of Herodii {Cochleariidce). The disputed cases of Eurypyga and Scopus have 

 already been mentioned. These and some other doubtful forms aside, the Herou series is 

 represented by the single. 



Family ARDEID^: Herons. 



In this family, as in Cochleariido', powder-down tracts reach their highest development; 

 although these peculiar feathers 0(^cur in some other birds, there appears to be then only a 

 single pair; so that presence of 2 or S pairs is probably diagnostic o{ Ardeidce. In the genus 

 Ardea and its immediate allies {Ardeina') there are 3 pairs, the normal number ; one on lower 

 back over hips, one on lower belly under hips, and one on breast, along track of furcula. In 

 Bitterns (Botaurince) the 2d of these is wanting. (In the Boat-bill, Cochlearius cochleariiis, 

 there is still another pair, over the shoulder-blades.) There are other pterylographic charac- 

 ters; in general, the tracts are extremely narrow, often only two feathers wide; there are lat- 

 eral neck tracts ; the lower neck is frequently bare behind. ^lore obvious characters are, 

 complete feathering of head (as couipared with Storks, etc.), except definite nakedness of lores 

 alone — the bill appearing to run directly into the eyes; a general looseness of plumage (as 

 compared with Limicolrc) , and especially frequent development of remarkably lengthened, or 

 otherwise modified, feathers, constituting the beautiful crests and dorsal plumes that ornament 

 many species, but which, as a rule, are worn only during the breeding season. These features 

 will suffice to determine Ardeida, taken in connection with the more general ones indicated 

 under head of Herodiones, and the following details : 



Bill longer than head, usually about as long as tarsus, straight, or veiy nearly so, more 

 or less compressed, acute, cultrate (with sharp cutting edges) ; upper mandible with a long 

 groove. Nostrils more or less linear, pervious. Head narrow and elongate, sloping down to 

 bill, its sides flattened. Lores naked ; rest of head feathered, the frontal feathers extending in 

 a rounded outline on base of culmen, generally to nostrils. Wings broad and ample ; inner 

 quills usually as long as primaries, folding over them when the wing is closed. Tail very 

 short, of 12 (usually) or 10 (in Botaurmce) soft broad feathers. Tibia? naked below (with rare 

 exceptions), sometimes for a great distance. Tarsi scutellate in front (with rare exceptions), 

 and sometimes behind, generally reticulate there and on sides. Toes long and slender; outer 

 usually connected with middle by a basal web, hinder very long (for wading birds), inserted 

 on the level of the rest. Hind claw larger and more curved than middle one (always ?) : middle 

 claw pectinate. 



The grou}) thus defined oflFers comparatively little variation iu form ; the very numerous 

 genera now in vogue have been successively detached from Ardea, the typical one, with which 

 some of them should be reunited. Night Herons (^Nijcticordx and Ntjctdiiassa) differ some- 

 what in shortness and especially stoutness of bill ; while Bitterns (^Botaurus and Ardetta), the 

 South American genera Tigrisoma, Zcbriliis, and a h'w others, are still better marked. There 

 are about lOU species, of some .'35 genera, very generally distributed over the globe, especially 

 abounding in torrid ami temperate zones. Those that penetrate to cold countries iu summer 

 are regular migrants; others are generally stationary. They are maritinn^ lacustrine, and 

 jialudicole birds, drawing their chief sustenance from animal substances taken from tlie water, 

 or from soft ground in its vicinity; such as fish, reptiles, testa<'eans, aud insects, captured by a 

 quick thrust of the spear-like bill, given as the bird stands in wait or wades stealtiiily along. 



