Is Aviculture a Science? 371


has not advanced far enough to enable its votaries to sex speci-

mens by external characters, but is dependant upon the more

or less reliable statement of the taxidermist who skinned the

specimen, can hardly be said to have got ahead of man}' other

branches of zoology. In this item of knowledge of external

sexual characters the aviculturist has advanced further than the

systematise and therefore in that branch of his legitimate study

has proved himself the more scientific worker.


Without doubt the system of careful measurements adopted

in the United States National Museum is doing much towards

throwing light upon sexual differences ; but, without knowledge

of the exact ages of the birds which are measured, that light

must be greatly obscured. We know that nestling birds have a

very wide gape and that the breadth of the bill gradually narrows

with age. This narrowing process has not ceased at the time of

the first moult, when many birds acquire their adult plumage ; at

this time also the young have not attained their full length, but

are noticeably smaller than their parents : now it is quite con-

ceivable that the young birds from the same nest might all fall

to the gun of a collector in one State, and when compared with

adult birds from another State might be described as a distinct

sub-species on the score of their smaller size and shorter

broader bills.


This being so, the more species that can be bred and

studied in captivity, the better will the systematic student be

equipped for comprehending the meaning of the various measure-

ments in his cabinet specimens. Without the assistance which

such information as the breeder might supply, the only chance

for the systematist, when searching for sexual differences, is to

pick out and compare the largest sexed examples from the

same locality.


Any addition to the knowledge of man is science : for any

man to assert that his work is scientific and the other man's is

not, when both are helping to educate the public, is unreasonable ;

his work may be tnore irksome and brain-wearing, but it is not

more scientific on that account.



