304 HERONS, STORKS, AND IBISES. 



it may be found either singly, in pairs, or in small companies. It always frequents 

 regions the most remote from human habitations, where it may be seen standing — 

 sometimes breast-deep — in the water by the side of some tall papyrus stem, and 

 frequently resting on one leg only. But seldom is this bird seen away from the 

 neighbourhood of tall reeds, although it sometimes takes its station on a white-ant 

 hill on the bank, and occasionally resorts to open reaches of the river. When first 

 disturbed by a boat, it will fly off slowly above the reeds with a great noise, and 

 again settle ; but if roused a second time, it rises high into the air, and will not 

 again return to its haunt until the danger is past. Its flight is not unlike that of 

 the marabou stork, but the heavy beak is generally kept resting on the crop. The 

 only sound it uttera is a loud snapping of the beak, in which respect it resembles 

 the storks. Its principal food is fish, in order to capture which the bird often 

 stands breast-deep in the stream with its enormous beak lowered to the surface of 

 the water ; while at other times several individuals will combine to drive the fish 

 towards the shallows by marching in a semicircle through the water, and making a 

 great flapping of their wings. It has been asserted that these storks will kill and 

 eat snakes ; but it is probable that the statement has arisen from their devouring 

 the fish known as the bisher (Polyjyterus), which the natives sometimes term a 

 water-snake. That dead carcases and carrion are also consumed appears to be well 

 ascertained. The breeding-season takes place during the rains; the nest being 

 situated on some slight elevation among the reeds, especially one surrounded on all 

 sides by water. Here the birds collect a vast quantity of stalks and water-plants, 

 often solidified with mud, so as to form an accumulation of about a yard in height. 

 The eggs, which are small in proportion to the size of the bird, have thick white 

 shells, which are, however, bluish when first laid, but become brownish as incuba- 

 tion progresses ; they are overlain with a chalky coating. Young taken from the 

 nest thrive well on a fish diet, and are easily tamed. 



The Hammer-Head. 



Family SCOPID^. 



' From a structural point of view the small brown African bird, known as the 

 hammer-head or umbre {Scopvus umbrella), is even more remarkable than the pre- 

 ceding, since it combines many features common to the herons and storks, and is 

 accordingly regarded by Mr. Beddard as nearly allied to the common ancestral 

 stork from which those two groups have sprung. It differs from the herons in the 

 absence of powder-down patches on the rump, and of pectination in the claw of 

 the third toe, as well as in having the angle of the furcula without any median 

 projection ; but it resembles them in having the rings of the bronchial tubes 

 incomplete behind, and closed with membrane. In some other parts of its internal 

 anatomy it agrees with the herons on the one hand and the storks on the other ; 

 but it differs from all herons except the boat-billed species in the shortness of its 

 triangular tongue, and thereby resembles the whale-head and the storks, while it 

 is peculiar in having large bare tracts on the sides of the neck. The hammer- 

 head measures about 25 inches in total length, and has a somewhat cylindrical 



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