The _arrectores pili_ exhibit very little evidence of control or interference from the action of the brain, but there is one region of one animal, like the Rosetta stone that set Champollion at work, where a very simple hieroglyph is recorded. I have been able to find no other in all the hairy mammals I have examined than that startling pattern which the back of the lion, shown in Fig. 37, sometimes displays. That well-formed patch of reversed hair of roughly triangular shape which is frequently found on the back of a lion has been described and, as I interpret this strange structure, it would seem clear that neural change in some examples of this species has led to so persistent contraction of the _arrectores pilorum_ over a certain area of skin, and that these have permanently reversed the normal and primitive slope of the hair. I have never found it present in a lioness, and not in all cases of male lions. It marks its possessor with the brand of a fierce and especially savage character, and he is not able to screen it from the eye of the Zoologist as well as Milady did her brand of shame, until that fatal day when D’Artagnan disclosed it. This pattern on a lion’s back is strangely reminiscent of the ridge of bristling hair we see on the corresponding region of a fierce dog’s back when he is infuriated. In the latter it may be said to have selective value, as perhaps also is the bristling hair on the head of a gorilla when enraged, much in the same way as the Chinese warriors sought to alarm their enemies by terrifying grimaces, or those terrifying tones and expressions of face which the Tyrant man, really a coward, is said by such as Miss Wisk to exercise over the women of his circle. We may present all these to the Pan-Selectionist, but inasmuch as the short, bristling hairs on the back of a lion are on the one hand hidden by the mane from an animal in front, and on the other are so small as to be seen quite close if at all, the survival-value of the reversed pattern of hair in question is quite outside the province of selection. It is so manifestly under the control of cerebral action, that it may be compared, as an undesigned experiment, with that of man in placing harness upon a horse, as to the power of cerebral action in producing structure. Though, as far as I can learn, it stands alone, it is difficult to believe that such a thing as a unique example occurs in nature, but it is interesting and suggestive from the Lamarckian point of view, and even the opposing counsel must admit that it is among indifferent structures. Facial Muscles of Expression.