Page:The Zoologist, 4th series, vol 5 (1901).djvu/82

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58
THE ZOOLOGIST

into the pouch, and in others eaten without that preliminary. It should be remarked, however, that Cockroaches, despite their size, submitted very tamely to their fate. On no occasion was foot, carpus, or thumb used to secure or dismember prey.

The insects eaten by any creature in captivity cannot be taken as a criterion of its food in a free state, but it may be worth while to note that, in addition to the moths already mentioned, the following, among others, were readily taken by the Bats:—Mamestra persicaræ, Leucania pallens, Hepialus humuli, H. sylvinus, H. hectus, Rumia cratægata, Urapteryx sambucata, Odontopera bidentata, Fidonia atomaria, F. piniaria, and Amphidasis betularia. The Bats appeared to be unable to see food if held but little more than an inch in front of them, and this was the case in natural twilight, as well as in an artificially lighted room. It is therefore very doubtful whether, in a free state, they would avoid a distasteful moth because its nauseous properties were advertised by its warning colours.

That certain insects were distasteful was clearly shown by the behaviour of one of the Bats. It seized a moth (Euchelia jacobææ) from my fingers, but dropped it immediately, shaking its head from side to side in evident disgust. Taking the moth in my fingers, I offered it again to the Bat, which declined to touch it, I then held the moth with a pair of forceps, which I generally used in feeding the Bats, as being less susceptible to their sharp teeth than were my finger-tips, and which were intimately associated with food in their minds. The moth was seized at once, but dropped immediately with repeated signs of disgust, and I could not induce the Bat to take it a third time. On the two following evenings I offered it other moths of the same species, doing so before I gave it other food, in order to make sure that it was hungry, but it would not touch them, although it sniffed at them, and probably recalled their nauseous qualities by its sense of smell. On another occasion an example of Abraxas grossulariata was seized twice, and then dropped with every appearance of disgust, and I could not get the Bat to touch it again.

Two other moths (Spilosoma menthastri and S. lubricipeda) appear to be unpalatable, but in a lesser degree. The first time I offered the Bat a menthastri, it seized and ate it without