on the nest; but, so far as I can ascertain, this bird has never yet been heard to mimic the note of even another genus, and still less would it be likely to reproduce the note of a reptile, and a note which probably it had never once heard. For Snakes do not hiss, as birds sing, for amusement or occupation. Probably they never hiss at all, except in combat. This is at least true of the Common Snake (natrix), and the Viper (berus), both of which I have had (numbers of them) in captivity. The Common Snake, even when the sexes unite, utters no audible vocal sound, and, when angry with another of its species, it only shakes or rattles its tail a little; and the Viper seems to be equally silent. Both of these animals make much more noise by their rustling through herbage than by their vocal efforts, except on the special occasion of combat. I have seen the Common Snake feed, say, a thousand times, and never heard a hiss from it then, though sometimes there would be a slight expulsion of air, causing a sound like a little coughing, while a Newt or fish was being swallowed. The Blue Tit must therefore be as ignorant as a cockney fowl, so far as the hissing of Snakes is concerned.
The hissing of birds would therefore seem to be an inherited expression of rage, derived from a very remote ancestry.
With regard to butterflies perching in positions where they are inconspicuous (Zool. 1899, p. 230), I have often observed that the Common Blues are fond of sleeping not only on grass-stems (as recorded by Mr. Cornish), but also on the dead and dry seed-heads of plants, on which they are not noticeable. I have a note of once finding quite a number of Blues (eight or nine; the MS. is not with me) sleeping at evening on one small dead flower-head, which they would never have noticed in the sunny hours of day.
A Peacock Butterfly (Vanessa io) that lived one summer in a garden where I was at Stroud, spent the day at one side of the garden amongst the flowers, and at evening, or when the weather darkened, it entered the shelter of an upper branch on the shady side of a cypress tree on the other side of the garden, and amongst the black stems the insect was wholly invisible. At other times it never alighted on a cypress. The Peacock does not always choose such a dormitory. I have generally found it prefer the overhanging ledges of banks. The Red Admiral (V. atalanta) I
