Chap. XYIIT. CHANGED CONDITIONS. 137 



and Sweden, there can be little doubt that, if possible, they would 

 have been propagated. In the Jardin des Plantes, no bird of prey 

 has been known to couple. 33 No hawk, vulture, or owl has ever 

 produced fertile eggs in the Zoological Gardens, or in the old Surrey 

 Gardens, with the exception, in the former place on one occasion, 

 of a condor and a kite {Milvus niger). Yet several species, namely, 

 the Aquila fusca, Hal-iwtus leucocephalus, Falco tinnunculus, F. sub- 

 buteo, and Buteo vulgaris, have been seen to couple in the Zoological 

 Gardens. Mr. Morris 31 mentions as a unique fact that a kestrel 

 {Falco tinnunculus) bred in an aviary. The one kind of owl which 

 has been known to couple in the Zoological Gardens was the Eagle 

 Owl {Bubo maximum) ; and this species shows a special inclination 

 to breed in captivity; for a pair at Arundel Castle, kept more 

 nearly in a state of nature " than ever fell to the lot of an animal 

 deprived of its liberty/ 5 35 actually reared their young. Mr. Gurney 

 has given another instance of this same owl breeding in confinement ; 

 and he records the case of a second species of owl, the Strix passer ina, 

 breeding in captivity. 36 



Of the smaller graminivorous birds, many kinds have been kept 

 tame in their native countries, and have lived long ; yet, as the 

 highest authority on cage-birds 37 remarks, their propagation is 

 " uncommonly difficult." The canary-bird shows that there is no 

 inherent difficulty in these birds breeding freely in confinement ; 

 and Audubon says 38 that the Fringilla (Spiza) ciris of North 

 America breeds as perfectly as the canary. The difficulty with 

 the many finches which have been kept in confinement is all the 

 more remarkable as more than a dozen species could be named 

 which have yielded hybrids with the canary; but hardly any 

 of these, with the exception of the siskin ( Fringilla spinus), have 

 reproduced their own kind. Even the bullfinch (Loxia pyrrhula) 

 has bred as frequently with the canary, though belonging to 

 a distinct genus, as with its own species. 39 With respect to the 

 skylark (Alauda arvensis), I have heard of birds living for seven 

 years in an aviary, which never produced young; and a great- 

 London bird-fancier assured me that he had never known an 

 instance of their breeding ; nevertheless one case has been recorded. 40 

 In the nine-year Eeport from the Zoological Society, twenty-four 



33 F. Cuvier, ' Annal. du Museum,' 38 'Ornithological Biography,' vol. 



torn. ix. p. 128. v. p. 517. 



3i ' The Zoologist.' vol. vii.-viii., 39 A case is recorded in ' The Zoo- 



1849-50, p. 2648. logist,' vol. i.-ii., 1843-45, p. 453. For 



35 Knox, 'Ornithological Ramhles the siskin breeding, vol. iii.-iv., 1845- 

 in Sussex,' p. 91. 46, p. 1075. Bechstein, ' Stuben- 



36 'The Zoologist,' vol. vii.-viii., vogel,' s. 139, speaks of bullfinches 

 1849-50, p. 2566 ; vol. ix.-x., 1851-2, making nests, but. rarely producing 

 p. 3207. youno;. 



37 Bechstein, < Naturgesch. der Stu- 40 Yarrell's < Hist British Birds, 

 benvogel,' 1840. s. 20. 1839, vol. i. j>. 412. 



