Mr. R. Swiiihoe's Ornithological Notes made at Chefoo. 435 



15. White-rumped Swift. Cypselus pacificus. 



Swifts were at Chefoo before iis, and were to be seen every 

 fine day flying in parties bigh in the air, and in cloudy weather 

 darting about near houses and round the summits of hills. 

 At sundown I noticed they went seawards, and roosted in the 

 cliffs that bordered the sea. On the 22nd June, Constable 

 Webster went out collecting for me to the North Hock, a 

 small rocky islet about fifteen miles to seaward of the harbour. 

 He found the island girt with rocky cliffs, which he had much 

 difficulty in scaling by means of the oars of the boat. On the 

 top, about 100 feet elevation, was a grassy flat. In the clefts 

 and crannies of the rocks he found many nests^ off which he 

 poked the owners, and brought to me a dozen of them alive 

 in a cage. They were individuals of the bird under notice 

 of both sexes (five males and seven females), showing that 

 both males and females take their turn in incubation. Some 

 of these had an extraordinary four- winged gad-fly about their 

 feathers. The nests were small for the size of the bird, shaped 

 like three-quarters of a saucer, with its broken side adhering to 

 the rock, and in some cases resting its under surface on a pro- 

 jecting ledge. One was apparently a nest of the year, con- 

 sisting of a shallow saucer, nearly 4 inches in greatest breadth, 

 thicker behind than in front, and constructed of refuse straw 

 and a few bits of catkins and feathers, all strongly aggluti- 

 nated with a gelatinous matter, doubtless the bird^s saliva. 

 Another was perhaps the accumulation of six years, consisting 

 of six nests one placed above another and strongly glued to 

 it. Fucoids and a little earth formed the foundation of the 

 lowest of the series. The eggs contained in all were two in 

 number, the fresh ones pinkish white until blown, when they 

 became an unpolished white. Many were hard-set, containing 

 advanced embryos, and then showed externally dull white. 

 They average in length 1-2 inch, by 7 in breadth. This 

 species figures in the ]\IS. Illustrations as the " Iron-footed 

 Swallow.'' Pallas (Zoograph. Rosso-Asiat. i. p. 539) decides 

 after some hesitation to consider this only a var. |S of Cypselus 

 apus, and speaks of its breeding in company with the Black 

 Swift in abundance on the rocks about Lake Baikal. Had 



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