Mr. R. Swinhoe on Formosan Ornithology. 299 



bases and the laterals for a great part of their length being 

 white. Under-parts deep bluish grey, striated and mottled 

 with white. As the bird gets older, the mottling and white wing- 

 spots disappear and the white on the tail contracts. It is in this 

 young plumage the R. lineoventris, Hodgs. 



The female, I believe, always carries a partially immature 

 plumage. She is usually of a dingy smoke-grey, rather bluer 

 on the upper parts. Chin whitish. The under-plumage more 

 or less obscurely mottled. Vent, basal half of lateral rectrices 

 and a greater or less portion of all the others, and a narrow band 

 on the upper tail-coverts white. Rest of tail sepia. Wings the 

 same, margined paler. 



60. RUTICILLA AUROREA (Pall.). 



A few of these may be seen in the low country in winter. 



61. Drymceca extensicauda, Swinhoe, Ibis, 1860, p. 50. 



I have a series of this species both from South and North 

 Formosa. They are undistinguishable from the South-China 

 bird, except in being rather larger, and having usually more 

 robust bills. The bill in this bird, which is light in winter, 

 becomes almost entirely black in the breeding-season. 



They are found throughout all the low country of Formosa, 

 aflfecting places covered with coarse long grass, about the tops of 

 which they flit and twitter, throwing their tails up and from 

 side to side as they spring up the long grass-blade. Their song 

 is merely a quick repetition of their usual twittering call-note. 

 They feed on small Dipterous caterpillars and other insects. 

 Their nests are very elegant little pieces of workmanship, con- 

 sisting of a deep cup with a canopy, entirely composed of fine 

 grass. When first made they are quite green, and elude well 

 the eye of search as they stand sustained between the stems of 

 long grasses. The bird lays from three to seven eggs of a light 

 greenish blue, spotted, blotched, and waved, chiefly at the larger 

 end, with various shades of chocolate-brown. They average 

 •55 by '48, but vary in size and shape, and the distribution of 

 the chocolate markings assumes all manner of fanciful forms. I 

 have a very large series, and they are, I think, the prettiest eggs 

 I have ever seen. 



