on Evidence afforded by Captive Birds.



59



bizarre in form and coloration renders those birds which are not

accustomed to it extremely cautious in their approach ; they stand

on tip-toe with neck lengthened, run round it in a circle, peck and

spring back ; if they actually feared it they would neither approach

nor peck. As for terrifying attitudes in caterpillars, I am certain

that no insectivorous animal pays the least attention to them, so if

the unfortunate creatures think that the assumption of the line of

beauty looks frightful they must be greatly deluded.


On the other hand, although insects which at one time are

rejected by birds sometimes become acceptable when subsequently

tried, it does not follow that a wild bird which had rejected an

insect that offended its taste would test its flavour a second or third

time and eventually develop a liking for it ; it is far more probable

that having once found it nauseous, it would subsequently ignore it

utterly. A confiding bird naturally tests, and either accepts or rejects

what its owner offers it, but it would not be likely to select what it

had already proved to lie unpleasing when other and palatable food

was to be obtained with equal ease.


If the larvee of any insect were entirely protected from all

insectivorous animals by form or colouring, they would undoubtedly

become so abundant as to be a scourge : if the larvae of Centra

and its allies were not eagerly accepted and devoured by the Titmice,

they might have become as great a nuisance, as the caterpillars of the

currant-moth Abraxas and its allies,which are generally rejected by

insectivorous animals ; but even A. grossulariata, which spiders will

not approach but cut out of their web as they often do wasps, is not

invariably refused by foreign birds in captivity, though for all we

know to the contrary it may generally be by birds in freedom.


Metallic colours seem to be attractive to birds and in an aviary

they never hesitate for a moment to chase and devour the most

metallic of our British moths ( Plus-ici chrysitis), nor do they hesitate

to peck, if they do not invariably devour, chrysalides of Vanessa

urticce with its metallic decorations.


Birds both wild and in aviaries are eager for spiders and devour

them in considerable numbers. I have seen a wild bird hover in

front of the web of Epeira diademata and pluck the little animal from

the middle of its home ; this in itself tends to prove that the mere



