THE OSPREY. 



159 



he has founded his assertion, that the hundred 

 and ei^rhty years of the raven are proved by 

 observation." 



Flourens continues: "Fontenelle quietly nar- 

 rates (for in this matter, he had almost the rijfht 

 not to be astonished at anj'thing,) the history of 

 a parroquet that lived, he says, nearly a hundred 

 and twenty years. This parroquet was brought 

 to Florence in 1833, by the Grand Duchess de la 

 Rovere d'Urbii o, when she came to marry the 

 Grand Duke F'erdinand, and the princess said 

 then that this parroquet was the oldest member 

 of her family; it lived at Florence nearly a 

 hundred years. 



"When we give to it, on the faith of the words 

 of the Grand Duchess," said Fontenelle, "about 

 twenty years, it will then have lived a hundred 

 and twenty years. This is, perhaps, not the 

 longest term of life of these animals; but it is 

 at least certain, from this example, that they 

 can attain it". 



"The swan has the advantage," said Buffon, 

 "of enjoying to an extremely advanced age its 

 quiet and charming existence. Every observer 

 accords to it a very long life; some even have 

 gone so far as to say three hundred years, which 

 is doubtless an exaggeration; but Willoughby, 

 having seen a goose, which, upon sure evidence 

 had lived a hundred years, did not hesitate to 

 Conclude from this case, that th« life of the 

 swan may and ought to be longer, both because 

 it is larger, and because it takes longer time to 

 hatch its eggs; incubation in birds correspond- 

 ing to the time of gestation in animals, and, 

 perhaps, having some relation to the time of 

 growth of the body, which is proportionate to 

 the duration of life. The swan is more than 

 two years in growing, and this is a long time, 

 for in birds the entire development of the body 

 is much quicker than in quadrupeds". 



"Willoughby infers, then, the long life of the 

 swan from that of the goose, which could be 

 proved to have lived a hundred years. 



"This certain proof of a hundred years, in the 

 case of the goose, reminds us of the hundred 

 and eighty years of the raven, proved by obser- 

 vation, which Buffon speaks of". 



In all this, there was nothing fortified by 

 exact dates or precise references to the sources 

 of information. Many data were scattered 

 through the voluminous literature of ornithology 

 but no one had brought such data together. At 

 length, Mr. J. H. Gurney, the distinguished 

 ornithologist of Norwich, (England,) undertook 

 the task, and the memoir originally published 



in The Ibis and now republished, with many 

 modifications and additions, in The Ospkev is 

 the result. The enumeration is not exhaustive, 

 but it is very u.seful, and furnishes a basis for 

 generalization, to some extent. at least. 



Mr. Gurney pas.ses over in silence the records 

 of Buflfon and others mentioned by Flourens. 

 Doubtless he regards them as unverified state- 

 ments not worthy of association with those he 

 tabulates. 



Howconsiderable the advance in Mr. Gurney's 

 article is may be inferred from the fact that in 

 Prof. Ray Lankesters work "On Comparative 

 Longevity" (ISTili only sixteen forms were enu- 

 merated in the body of the text, (eleven on the 

 authority of Leopold Grindon,) and most of them 

 were queried as uncertain. Seven additional, 

 but imperfect observations were noticed in a 

 note Communicated by Darwin. 



Hut almost a century ag-o-in the clo.sing year 

 (18001 of the eighteenth century— a list of spe- 

 cies who.se ages had been ascertained was given 

 by a French naturalist— Daudin. In Daudin's 

 almost forgotten work, Traite Elementaire et 

 Complet d' Ornithologie, (p. 126.) twenty-seven 

 species are enumerated in a "Table de la duree 

 de la vie de quelques oiseaux" compiled from 

 Buffon and others. The ages assigned were in 

 almost cases rea.sonable and in conformity with 

 those since a.scertained. Daudin. it is true, 

 gives 300 years to the Swan, but he appends an 

 exclamation of doubt -■■!" 



It is evident that there are no such ratios be- 

 tween the size of a bird and its duration of life, 

 its period of embryological development, and its 

 period of adolescence as prevail among mam- 

 mals. Nevertheless, there are indications that 

 there is a tendency at least towards an exten- 

 sion of the duration of life among some large 

 birds, as those of prey, and towards the retarda- 

 tion of the development of the full livery of 

 perfect maturity. Even this, however, is not 

 perfectly proved, and there are indications, on 

 the other hand, that such tendencies may be a 

 family or group habit. 



Much remains to be done yet before positive 

 generalization can be indulged in certainly. 

 Such observations should be made, and can be 

 made by many ornithologists, whose opportu- 

 nities for study in other directions may be 

 limited. Let us hope that they may be attempt- 

 ed. It is noteworthy that in the long list of 

 species catalogued by Mr. Gurney, only one re- 

 ference is given to an American record— that 



