Tattooing often reveals the psychology, habits, and vices of the individual. The tattooing on pederasts usually consists of portraits of those with whom they have unnatural commerce, or phrases of an affectionate nature addressed to them. A pederast and forger examined by Professor Filippi was tattooed on his forearm with a sentimental declaration addressed to the object of his unnatural desires; a criminal convicted of rape was covered with pictorial representations of his obscene adventures. From these few instances, it is apparent that these personal decorations are of the utmost value as evidence of hidden vices and crimes.

Wrinkles. We have already spoken of the abundance and precocity of wrinkles in born criminals. They are also a characteristic of the insane.

The following are of special importance: the vertical and horizontal lines on the forehead, the oblique and triangular lines of the brows, the horizontal or circumflex lines at the root of the nose and the vertical and horizontal lines on the neck. (The ferocious leader of a band of criminals at twenty-five, and a savage murderer under thirty years of age.)

Beard. The beard is scanty in born criminals and often altogether absent in epileptics. On the other hand, it is common in insane females and in normal women after the menopause. Degenerates of both sexes frequently manifest characteristics of the opposite sex in the distribution of hair on the body. A tuft of hair in the sacro-lumbar region, suggestive of the tail of the mythological faun, is frequently found in epileptics and idiots, and in some cases the back and breast are covered with thick down which makes them resemble animals.

The hair covering the head is generally thick and dark, the growth is often abnormal with square or triangular zones growing in a different direction from the rest, or in small tufts like those inserted in a brush. Still more frequently do we find anomalies in the position of the vortex, or that point whence the hair-growth diverges circularly, which in normal persons is nearly always situated on the crown. In degenerates it is frequently on one side of the head and in cretins on the forehead. Precocious greyness and baldness are common in the insane criminals, and cretins, on the contrary, show these initial signs of senility at a much later period than normal persons.

Teeth. The greatest percentage of anomalies is found in the incisors; next come the premolars, the molars, and lastly the canines. In criminals, especially if epileptics, the middle incisors of the upper jaw are sometimes missing and their absence is compensated by the excessive development of the lateral incisors. In other cases the lateral incisors are of the same size as the middle ones, and sometimes the teeth are so nearly uniform that it is difficult to distinguish between incisors, canines, and molars, a circumstance which recalls the homodontism of the lower vertebrates. After the incisors, the premolars show the greatest number of anomalies. While in normal persons they are smaller than the molars, in degenerates they are frequently of the same size or even larger. Supernumerary teeth, amounting sometimes to a double row, are not uncommon. In other cases there is extraordinary development of the canines. Inherited degeneracy from inebriate, syphilitic, or tuberculous parents frequently manifests itself in rickety teeth with longitudinal and transverse striæ or serration of the edges, due to irregularities in the formation of the enamel. In idiots and epileptics, dentition is often backward and stunted; the milk-teeth are not replaced by others, or are almond-shaped and otherwise of abnormal aspect.

Ears. The ears of criminals and epileptics exhibit a number of anomalies. They are sometimes of abnormal size or stand out from the face. Darwin's tubercle, which is like a point turned forward when the helix folds over, and turned backward when the helix is flat, is frequently encountered in the ears of degenerates. The lobe is subject to a great many anomalies, sometimes it is absent altogether, in some cases it adheres to the face or is of huge dimensions and square in shape. Sometimes the helix is prolonged so as to divide the concha in two. Idiots often show excessive development of the anti-helix, while the helix itself is reduced to a flattened strip.

Eyes. The eyebrows are generally bushy in murderers and violators of women. Ptosis, a species of paralysis of the upper lid, which gives the eye a half-closed appearance, is common in all criminals; but more frequently we find strabismus, a want of parallelism in the visual axes, bichromatism of the iris, and rigidity of the pupils.

Nose. In thieves the base of the nose often slants upwards, and this characteristic of rogues is so common in Italy that it has given rise to a number of proverbs. The nose is often twisted in epileptics, flattened and trilobate in cretins.

Jaws. Enormous maxillary development is one of the most frequent anomalies in criminals and is related to the greater size of the zygomæ and teeth. (See [Fig. 27].) The lemurian apophysis already alluded to is not uncommon.