Sir,—

From the recent investigations of Mr Tegetmeier, and from those of the older naturalists, most people who keep Polish fowls are aware that the tuft of feathers on their heads is supported by an extraordinary, almost hemispherical, protuberance of the front part of the skull.² This protuberance is accompanied by an equal change in the shape of the brain. Pallas and some of the older writers describe the Polish fowl as, in consequence, stupid;³ but Mr Tegetmeier has shown that this is a mistake. The experience of many savage races of man proves that the external shape of the brain may be greatly modified by pressure, without the intellectual faculties being affected. Nevertheless, after having recently examined the skulls of Poland fowls, I am astonished that such profound changes should have produced no effect on the mental powers of these birds. Bechstein, writing in Germany in 1793, says, that although it is an error to suppose that fowls with such misformed skulls are stupid, yet that he had a white-crested black Poland which “was crazy, and which all day long wandered anxiously about.”⁴ I, also, formerly had a silver-spangled Poland which was curiously affected; she sometimes seemed lost in reverie, and allowed any one to approach so as even to touch her; she was solitary in her habits, and was extraordinarily deficient in the sense of direction. I have seen her stray hardly more than a hundred yards from her feeding place, and become completely lost; and she would then continue obstinately to try to get through a fence in a direction exactly opposite to her home. Now, will any of your correspondents who have long kept tufted fowls have the kindness to state whether they have observed any clear signs of deficiency in the mental powers of any of their birds? or, has any one ever seen a “crazy fowl,” such as Bechstein describes, in any other breed?⁵

Charles Darwin. | Down, Bromley, Kent.