Mr. R. Swinhoe on Formosan Ornithology. 273 



and legs in most, if not all, the species of this genus are of the 

 same perishable colours. 



Length about 7— in. ; wing usually about 4 in. (out of eight 

 specimens the longest wing measures 4^^^, the shortest 3-py) ; tail 

 2^, of 12 feathers, nearly of equal length. 



Adult : irides deep brown ; general plumage sepia-brown, 

 blacker on the head and under parts, and tinged with yellowish 

 brown on the back and rump. The Japanese Dipper is said, 

 in the ' Fauna Japonica,' to have the 2nd primary quill nearly 

 equalling the 3rd, which is the longest of all. In all ours the 

 2nd is ^ shorter than the 3rd, and the 3rd and 4th are equal 

 in length, the 5th being a little shorter. If this is a sufficient 

 character, perhaps ours is a distinct species, as by isolation it 

 should ere this have become, it being a resident on the island, 

 and not migratory. When I first discovered the bird, on my 

 second visit to Formosa in 1857, 1 described it as probably new, 

 under the term Hydrohata marila. It may be found, on compa- 

 rison with the true Cinclus pallasi, Temm., to be distinct enough 

 to require a name of its own. 



This bird must nest early, for in April fully-moulted young 

 of the year were already abroad. In this stage the irides are 

 lighter, the inside and angle of mouth light yellow, the bill 

 flesh-brown, and the legs purplish flesh-colour with a slaty wash. 

 The upper parts are deeper brown than in the adults, being ob- 

 scurely spotted on the back and rump with a lighter reddish 

 brown ; these spots are more distinct on the upper tail-coverts, 

 which are entirely tinged with reddish ; most of the feathers of 

 the upper parts are margined with black. Feathers of the wings 

 edged and tipped with light sepia and whitish, the ground-colour 

 being much blacker than in adult wings. Throat whitish, finely 

 striated with sepia. The rest of the under parts deep blackish 

 sepia, the feathers on the breast and flanks being margined with 

 light reddish brown, on the axillaries and belly with whitish. 

 I have taken this description of the immature bird from two 

 specimens in my collection, procured in N.W. Formosa in April. 



This bird is usually met with on the mountains some 2000 or 

 more feet above the sea, frequenting the sides of solitary cas- 

 cades, which abound in the hilly parts. There, like the rest of 



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