154 



#1 



STERILITY PROM 



Chap. XVIII. 



In the 



/ 



(Milvus 



* 



be little doubt that, if possible, they would have been propagated. 

 Jardin des Plantes, no bird of prey has been known to couple. 31 N ha rk 

 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 o ' 



* ■, ,.. ,„., .^ Yet several species, 



, Falco tinnunculus, F. sub- 

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

 Gardens. Mr. Morris 32 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 

 maximus); 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," » 

 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 passerina, breeding in captivity. 34 



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 35 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 36 that the Fringilla 



(Sp 



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. 37 

 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. 38 In the nine- 

 year Report from the Zoological Society, twenty-four incessorial species 

 are enumerated which had not bred, and of these only four were known 

 to have coupled. 



Parrots are singularly long-lived birds ; and Humboldt mentions the 

 curious fact of a parrot in South America, which spoke the language of 



31 F. Cuvier, 'Annal. du Museum,' 

 torn. ix. p. 128. 



32 ' The Zoologist,' vol. vii-viii. , 1849- 

 50, p. 2648. 



33 Knox, ' Ornithological Rambles in 

 Sussex,' p. 91. 



34 ' The Zoologist,' vol. vii.-viii., 1849- 

 50, p. 2566; vol. ix.-x., 1851-2, p. 



3207. 



35 Bechstein, 'Naturgesch.der Stuben- 

 vogel,' 1840, s. 20. 



36 • Ornithological Biography,' vol. v. 

 p. 517. 



37 A case is recorded in ' The Zoolo- 

 gist,' vol. i.-ii., 1843-45, p. 453. For 

 the siskin breeding, vol. iii.-iv., 1845-46, 

 p. 1075. Bechstein, < Stubenvogel,' s. 

 139, speaks of bullfinches making nests, 

 but rarely producing young. 



38 Yarrell's 'Hist. British Birds,' 

 1839, vol. i. p. 412. 



f) 







