274 Mr. R. Swinhoe on Furmosan Ornithology. 



its tribcj it feeds on freshwater insects, Crustacea, and Mollusca. 

 I met with it on one of my rambles into the hills. It was 

 perched on a large slab of rock that stood in a running stream. 

 It kept throwing up its tail like a Wren, and, hopping to the 

 edge of the stone, dashed into the water ; in a few seconds it 

 reappeared at the surface and regained the rock. Till then I 

 was not quite sure what bird it was ; there was no longer any 

 mistake. My time was short, and I could watch no longer ; so I 

 secured my specimen and went my way. It was a likely place and 

 season for its nest, but in my hurried search I could not detect it. 



33. Petrocincla manilensis (Bodd.). 



In Formosa you find this species as it is generally known, with 

 blue upper plumage and breast and red belly. In all my nume- 

 rous specimens the colours are always uniform. But in Amoy the 

 red belly is by no means constant ; I have several skins entirely 

 blue, and others again with all proportions of red and blue. This, 

 however, does not appear to be the case in the Formosan bird ; so 

 we will not here discuss the question of the validity of the species. 



The female retains the mottled plumage through life ; but the 

 young male in the first autumnal moult shows a good deal of 

 blue on the back and throat, and red on the lower parts : the 

 plumage becomes more defined in the following spring ; but the 

 mottles do not entirely disappear till the close of the second year, 

 and often not then. 



Length. Wing. Tail. 



Male 81 in. 5-[^ in. Sxlj in. 



Female 8^ 4^^, 3^% 



Both sexes vary somewhat in size, as also in the length of the 

 wing. My measurements are from full-sized examples. 



This bird is partial to rocky hills near the sea. Its song is 

 very sweet, and is often uttered on the wing. It builds its nest 

 in the hollows and clefts of rocks and walls, adapting it to the 

 shape of the chosen locality, and constructing it of fine flexible 

 twigs, lined with fine grass, wool, and occasionally a few feathers. 

 These are loosely put together, without much art. It lays from 

 three to five pale greenish-blue eggs. In autumn, after the first 

 moult, the young leave the hills and frequent the housetops of 



