occupied by Birds in Incubation. 87 



Order, having a decidedly longer period than any of their 

 neighbours. 



The Pica7'ice do not appear to differ to any marked extent 

 from the Passeres in the duration of incubation. Should 

 the data now brought together be confirmed by future 

 observations, the Picarian periods will be slightly the longer 

 of the two, when measured with due regard to the size 

 of the eggs. Such tiny creatures as the Ruby-throated 

 and the Black Humming-bird do not, according to Audubon 

 and Audebert, take less than 10 to 13 days, and the larger 

 forms of Woodpecker and Kingfisher, and the Roller, take 

 from 18 to 20. 



If the information as to the Parrots {Psittaci} be correct, 

 they hatch in less time than I should have expected in view 

 of their reputed longevity, for I believe there is an intimate 

 connection between the period of incubation and the average 

 lifetime of the bird. 



Though the statements regarding the Owls {Sti'iges) are 

 rather conflicting, the weight of evidence is all in favour of 

 a long period of incubation, an egg of the Long-eared Owl, 

 which is scarcely bigger than that of the Ring Dove, taking 

 fully 26 days to hatch in the incubator^. The Eagle Owl aud 

 the Snowy Owl may be held to take about 32 or 33 days. 



The Diurnal Birds of ~Prej (the Ace ipitres) are, undoubtedly, 

 also a long-period race, notwithstanding some of the records 

 quoted. For instance, Tiedemann's statement that the Pere- 

 grine hatches in 18 to 19 days must be set aside as erroneous, 

 and so likewise must Elwes's 21 days for the Golden Eagle. 

 In all probability the former bird sits not less than 4 weeks, 

 and the latter nearer 5. I regret that I failed to hatch any 

 Hawks' eggs in the incubator, but the Rev. Julian Tuck's 

 observations on the Kestrel, made at my special request, on 

 a nest in the tower of the church at Bury St. Edmunds in 

 the spring of 1889, proves the time in that species to be 

 little, if at all, short of 4 weeks. 



Among the Steganopodes the Solan Goose has a remarkably 



* Several other eggs of this Owl were hatched, but, not being perfectly 

 fresh when obtained, have not been entered in the Table, though the 

 periods were quite in keeping with the one above mentioned. 



