492 IBIS. IBIS. 



between Ibis and Numenius there is scarcely any interval. 

 With respect to the digestive organs, the Ibises nearly cor- 

 respond with the Numenii, and differ entirely from the 

 Herons, their oesophagus being the only part that in width 

 approaches to theirs. In the Herons the stomach is large, 

 round, and membranous, the intestine very long and ex- 

 tremely slender, the cceca wanting; whereas in the Ibises 

 the stomach is of small capacity, but very muscular, the 

 intestine of moderate length and rather wide, and the cosca 

 present, although very small. The tongue of the Ibises is 

 shorter than that of the Curlews, and resembles that of the 

 Spoonbills, but differs entirely from that of the Herons. 



The sexes are similar, the female being only a little 

 smaller. The young, however, are differently coloured. The 

 Ibises belong to the tropical and warmer regions of both 

 continents, or if some reside also in the temperate parts, 

 they migrate southward in autumn. While in the form 

 of the feet, and also in some measure in that of the 

 wings and tail, they bear a considerable resemblance to the 

 Herons, they also resemble them somewhat in their mode 

 of walking and flying. According to M. Savigny, the two 

 species which occur in Egypt feed on worms and small 

 fresh-water mollusca, but never attack serpents, as had long 

 been believed. They are generally gregarious. Both have 

 a powerful and elevated flight, their pectoral muscles being 

 very thick ; they fly with the neck and feet extended hori- 

 zontally, and at intervals simultaneously emit low and very 

 hoarse cries. When they have alighted on newly uncovered 

 places, they may be seen for hours in the same spot, 

 unceasingly thrusting their bill into the mud. They never, 

 like our Curlews, start off and run with rapidity, but always 

 advance step by step. M. Audubon states that the White 

 Ibis nestles in trees or bushes, like some Herons, laying 

 three spotted eggs. The young, at first covered with thick 

 down, often leave the nest long before they are able to fly, 

 and are easily caught. The flight of this species, he says, 

 is rapid and protracted, and at times, like the Red Ibis and 

 Tantalus Loculator, it rises to a great height, performing 

 various evolutions. It feeds on crayfish, worms, and mollusca. 



