§ 1. Cranial and Cerebral Characteristics.
Considerably greater importance was formerly attributed to the shape and measurements of the head than we can now accord to them, although the subject still retains much interest. A vast quantity of data has accumulated concerning the heads of criminals; some of the results are contradictory, but certain definite conclusions clearly emerge.
The average size of criminals’ heads is probably about the same as that of ordinary people’s heads; but both small and large heads are found in greater proportion, the medium-sized heads being deficient. The same is true, as Tigges and others have shown, of the insane, though among these the larger preponderate to a greater extent. Thieves more frequently have small heads; the large heads are usually found among murderers.
Nothing very definite can be said of the cephalic indices save that they are frequently an exaggeration of those of the race to which the criminal belongs; those of long-headed race being sometimes very long, and those of broad-headed race sometimes very broad; the Corsican criminal being often very dolichocephalic, and the Breton criminal often very brachycephalic.
There is a generally recognised tendency to the pointed (oxycephalic) or sugar-loaf form of head. Though this form is probably, as Benedikt points out, an effort at compensation, it is an effort that testifies to defective organisation. The opposite defect of low or flat-roofed skull is also found among criminals, and is characteristic of degeneration. Lauvergne, in his old book on criminals, has a vivid and picturesque sketch of a variety of this kind of head, which he called the satanic type, and which he found among many of the worst criminals: “Such are the heads which painters throw into their pictures, and call ‘heads of the other world.’ I have recognised them in mediæval pictures, and in all the museums in which the products of early art are preserved. You will see them on old cathedrals, in which devils play a part, or wherever the artist has received some diabolical inspiration, as in the Campo Santo at Pisa. One cannot, indeed, better represent the genius of evil, Satan, the fallen angel, than by giving him such a head.... Behind the frontal bones the head seems to have been tied with a band to compress it around and to force the swelling of the hemispheres upwards and backwards. It is the head vulgarly called sugar-loaf. When it is complete, that is to say, when it presents a prominent base supporting an inclined pyramid, more or less truncated, this head announces the monstrous alliance of the most eminent faculty of man, genius, with the most pronounced impulses to rape, murder, and theft.” Benedikt regards the bilateral elevation of the sagittal suture as, though rare, “significant of profound perversity of brain function.” He also regards disproportionate development of the occipital part of the skull as a characteristic mark of degeneration.[17] It appears that the posterior half of the skull varies much more in different individuals than the anterior half.
The orbital capacity has been noted by Lombroso and others to be frequently larger than normal (as among birds of prey and some savages), especially among thieves. There is marked exaggeration of the orbital arches and frontal sinuses which may be related, at all events in the cases of individuals living in the country, with energy of the respiratory system.
Receding foreheads, very commonly observed among criminals, have always been regarded as evidence of low mental and moral organisation, not without reason, though it must be remembered, as Ten-Kate and Benedikt point out, that the breadth, vaulting, and general size of the head must be taken into consideration. Many men of marked intellectual power have had receding foreheads.
Tenchini has pointed out (and the observation has since been confirmed) that the frontal crest is often stronger and more prominent in criminals. In normal skulls he found it 3-4 millimetres in length; in criminals frequently 5-6 mm. It is also larger in the insane and lower races, and relatively larger in orang-outangs. It may signify precocious union of the two parts of the frontal bone with consequent arrest of brain development.
The presence of a median occipital fossa has been specially noted by Lombroso, sometimes in connection with hypertrophy of the vermis of the cerebellum, as among the lower apes, in the human fœtus between the third and fourth months, and in some lower races.
Lack of cranial symmetry is one of the most marked features of the criminal skull, although it has not often at present been subjected to exact measurement.[18] It must be remembered that every skull, criminal or non-criminal, is deficient in strict symmetry (and, indeed, every part of the body likewise), and that statistics therefore are here of little value; it is simply a question of the amount of asymmetry; and two observers going over the same series of skulls would almost certainly come to different conclusions. They would probably, however, both find the proportion of asymmetrical heads greater in the criminal than in the ordinary series.