282 



A VES ORDER ARDEIFORMES. 



Fig. 42. THR SHOE-BILLED STORK 

 (Balceniceps rex). 



region, but instead of being widely distributed like the Hammer-head, 



the Shoe-bill is confined to the districts of the Upper Nile. The shape of 



the bill, with its dertral hook, 

 The Shoe-billed is sufficient to distinguish 



Storks. -Sub order Balceniceps at a glance. The 



Batenitipiiide*. genus further possesses two 



powder-down patches like the 



Herons, but differs from the latter birds in the 



absence of any pectination on the middle claw, 



and in its Stork-like furcula. Taking all points 



of its anatomy into consideration, the balance of 



evidence seems to be in favour of the alliance of 



Balceniccps with the Storks. 



Von Heuglin considered the " Abu-mask up " 



or Shoe-bill to be a kind of Marabou, and an 



inhabitant of the Upper Nile regions, such 



as the Saraf River, the Lower Kir district, 



and the Gazelle River, and the countries lying 



between. It is everywhere a shy bird and 



decidedly scarce, its habits being Stork-like, 



standing on one leg and feeding on fish. Its 



only note seems to be a snapping of the bill 



like that of a Stork. 



One of the chief differences between the Herons and the Storks is the 



pectinated claw on the third or middle toe, and another difference is the posi- 

 tion of the hind toe, which, in 

 The Herons. tne Storks, is elevated above 

 Sub-order the level of the other toes, 



Herudiones. and in the Herons is on the 

 same level as the latter. 



The median process on the furcula has been 



already alluded to. The Herodiones may be 



divided roughly into the Herons and the 



Bitterns. The former have twelve tail-feathers, 



and the latter ten. 



The true Herons comprise a large number 



of genera, all more of less closely connected 



together, but differing in certain constant 



peculiarities, which warrant their being separated 



as genera, or, at least, as sub-genera. Thus the 



Purple Heron of Europe is remarkable for its 



long middle toe, which is as long as the tarsus, 



and hence it is known as Phoyx purpurea. 



The genus Ardea, on the other hand, has the 



proportions of the toes different, the middle toe 



being shorter, and the tarsus longer than the 



middle toe and claw. Besides the pectinate or 



comb-like claw on the middle toe, our Common Heron (A. cinerea) has the 



tip of the bill serrated or furnished with saw-like notches along the cutting 



edge at the end of the upper mandible. 



The Common Heron is now to be found nesting in England only in 



certain heronries where the bird ia protected. The havoc which the bird 



Fig. 43. THE COMMON HBRON 

 (Ardea cinerea). 



