Mr. R. Swinhoe on Formosan Ornithologij . 257 
heavy, and the birds seemed in high spirits at the return of fine 
weather. They fluttered from branch to branch, and as they 
regained a footing, rocked backwards and forwards before re¬ 
covering their balance. It was in April, and they were all 
paired, the male being always distinguishable by his larger 
size and longer tail. In pairs they sang, or rather twittered, 
their notes kee-wee-kee, like sounds that might be produced by 
some metal instrument sadly out of tune. The male loudly 
sang his bar, and the female followed on a lower key. The 
male then fluttered his wings and began again; the female 
followed suit. In this manner the whole clump of tall, graceful 
bamboos looked alive with these birds, and resounded with their 
strange notes. Some pairs would start away and pursue one 
another, at first, with a smooth, skimming flight; then in an 
excited manner they would stagger along and, fluttering their 
wings, sing lustily their notes of love. 
18. Cotyle sinensis (J. E. Gray): Ill. Ind. ZooL t. 35. fig. 3. 
Hirundo brevicaudata , MacClell. 
This small, grey-breasted, short-tailed species is a summer 
visitant to all suitable localities in the south of China, and is also 
found in all parts of Formosa, frequenting the steep sandy banks 
of rivers, into which it bores long galleries, constructing at the end 
of these its cup-shaped nest, and depositing therein three white 
eggs. Its winter migrations extend to the plains of Hindostan, 
where, curiously enough, it is reported by observers to nest again 
in the heart of winter (see Horsfield and Moore’s List of Birds 
in the East Indian Museum, i. p. 96). This is, I believe, the 
only well-authenticated fact recorded of this long-suspected habit 
in migratory birds. It visits Formosa in April, and leaves again 
in October. 
Length 4^ in.; wing 3^; tail 1^, subfurcate. Upper parts 
greyish hair-brown; neck and breast much paler, dark on the 
sides of the breast. Wings and tail dark hair-brown; axillaries 
hair-brown. Belly and vent white. Bill, legs, and claws purplish 
brown; the feathered tuft in the joint between the tarsi and 
hind toe is wanting. 
Some fifteen miles up the Tamsuy River, in a long sand-bank, I 
yol. v. t 
