TKIBONYX CENTRALIS (Gould). 



BLACK-TAILED TRIlloXYX. Gbxus : Tribonvx. 



IT is a curious fact that while one species of the genus Tnhoin/.v should he so common in Tasmania, 

 the other should aever he seen then 1 . Mortier's Tribonyx is as stedfast in its affections to certain 

 Localities as the I Mack-tailed is casual and uncertain. It may he described as a bird of migratory habits, 

 but with do defined destination: it will suddenly appear somewhere where it may never before have been 

 seen, and disappear again as rapidly. 



Although it resembles the Gallinules in outward appearance, it really possesses a very different 

 structure, particularly in the form <>f the tarsi and toes, and in the tail, while its economy is equally 

 different. It is much inure terrestrial than aquatic, and is designated by some as simply "Moorhen," 

 which i> a better specific name than Black-tailed Tribonyx. 



Gilbert says of the bird that ''upon one occasion it visited the Swan River colony in myriads, 

 treading down and destroying whole fields of corn in a single night. The natives, not having seen them 

 before, attributed their appearance to the settlers, and for a long time termed them the 'white men's 

 birds.' After the harvest was over they nearly all disappeared as suddenly as they arrived. The natives 

 of the banks of the Upper Swan, on making enquiries respecting these birds of some of the tribes of the 

 interior, were told they came from the north." 



"This bird," says Captain Sturt, "appeared suddenly in South Australia in 1840. It came from 

 the north, fresh flights coming up and pushing on those which had preceded them. It was, moreover, 

 evident that they had been unaccustomed to the sight of man, for they dropped in great numbers in the 

 streets and gardens of Adelaide, and ran about like fowls. At last they increased so much in number 

 as to swarm on all the waters and creeks, doing great damage to the crops in their neighbourhood. They 

 took the entire possession of the creek near my house, and broke down and wholly destroyed about an 

 acre and a quarter of wheat as if cattle had bedded on it. They made their first appearance in November, 

 and left in the beginning of March, gradually retiring northward as they had advanced." 



"In the autumn of 1854," says Mr. Elsey, "the stations about the Mackenzie were besieged by 

 swarms of this species. They remained some time, then disappeared, and not a single specimen appeared 

 there for certainly the next three years." 



It is an ungainly bird, with strong muscular legs intended for speed, with which it runs so 

 rapidly that even on the parched plains destitute of grass or herbage, it would elude pursuit and hide 

 itself in the roots of large trees, or the shelving banks of a river. It rarely uses its wings, even when 

 pursued. 



The month of November is the breeding season, when a nest is made on the ground of soft 

 grass and rushes among the long grass-like rushes of the river side. The eggs are seven in number, of 

 a greenish ground colour, very minutely freckled all over with reddish brown specks, with a few large 

 blotches here and there over the shell. Length, 1 inch 8^ lines ; breadth, 1 inch 2^ lines. 



The food found in the thick muscular stomach consists of grain, seeds, and other vegetable 

 substances, shelled mollusks, insects, etc. 



Head and all under surfaces, dull brown with steely blue lights; flank feathers black, with an oblong 

 mark of white near the tips ; tail, black ; all upper surfaces, dappled olivaceous brown ; primaries, brown, 

 the outer one margined with white ; hides, orange ; upper mandible, beautiful pea-green, becoming rather 

 paler at the tip ; base of the lower mandible, light reddish orange ; the tip like that of the upper ; legs and 

 feet, deep brick red. 



Total length, 15 to 17 inches. 



Habitats: Derby (X.W.A.), Gulf of Carpentaria, Port Denison, Xew South Wales, Interior, 

 Victoria and South Australia, Western and South- Western Australia. 



