There is more evidence in favour of attaching some importance to the shape of the brain, to its relative development, to the condition and relations of its convolutions. Broca, Topinard, and many other eminent anthropologists and anatomists have attributed great value to these relations. Gall was perhaps the first to suspect their significance. Benedikt, in 1879, published some interesting generalisations on the brains of criminals which he had examined. He found special frequency of confluent fissures; that is to say, according to his own description, if we imagine the fissures of the brain to be channels of water, a swimmer might with ease pass through all these channels. Benedikt also found in the brains of his criminals that the frontal lobe frequently presented four convolutions, a peculiarity which he considered as a reversion to the carnivorous type; the investigations of Hanot and Bouchard confirmed these results. But Benedikt neglected to make an adequate comparison with the normal brain, and Giacomini, Corre, Fallot, and Féré have shown that these peculiarities are not very rare in ordinary subjects. The question of confluent fissures had before this time attracted the attention of Broca, and his conclusions may probably still be accepted:—“One or more of these communications,” he said, “do not prevent a brain from being at once very intelligent and very well balanced, but when they are numerous, and when they affect important parts, they indicate defective development. They are often seen in the small brains of the weak-minded and idiots, very frequently also in the brains of murderers, with this difference, that in the first case they are related to the smallness of the convolutions and of the brain generally; while in the second case they coincide with convolutions for the most part ample in size, and bear witness to irregularity in cerebral development.” Flesch studied the brains of fifty criminals, and found that every one presented some anomaly, sometimes of a remarkable character, as incomplete covering of cerebellum by cerebrum. He found two kinds of deviations common, one characterised by less richness of convolution than is found usually in ordinary brains, the other characterised by much greater richness of convolution than he had ever observed in normal brains. On the whole we may agree with Hervé, that “what the brains of criminals present, not characteristically but in common with those of other individuals badly endowed though by no means criminals, is a frequent totality of defective conditions from the point of view of their regular functions, and which renders them inferior.”[20]
Although a very considerable mass of evidence is now accumulating, we know considerably less of the brains of criminals than of their skulls. This is in large measure due to the fact that there is at present insufficient evidence regarding the condition of the normal and healthy brain, and unless controlled by careful series of observations on normal persons, observations on criminal brains cannot be interpreted.
The important matter of the vascular supply of the brain in criminals has yet received little attention, but a variety of pathological features have been found in the cerebral substance and membranes—pigmentation, degenerating capillaries, cysts, thickened and adherent membranes, the vestiges of old hyperæmia and hæmorrhages. Some of these conditions are found with great frequency, much oftener than in the insane; meningitis, for instance, being found, according to Lombroso’s experience, in 50 per cent. of the cases examined; while Flesch has obtained very similar results. The frequency of meningitis was noticed in some of the answers to my Questions, especially by one prison surgeon who wrote of “well-organised adhesions between the dura mater and vault of cranium, localised but more extensive than one would expect to find.” Unfortunately, he was unable to supply exact figures as to the frequency of such signs. It must be added, as a point of considerable importance, that in very few cases have these pathological lesions produced any traceable symptoms during life.
§ 2. The Face.
Prognathism has frequently been noted as a prominent characteristic of the criminal face, both in men and women. This is, however, a point that requires further study; giving due weight to racial characteristics, to the proportion of prognathous individuals among the general population, and to method and uniformity in measurement.
There is little doubt that the lower jaw is often remarkably well developed in those guilty of crimes of violence. The squareness and prominence of the jaw are obvious to the eye, and this is verified by weighing after death, as has been shown by Manouvrier. The average weight of the Parisian criminal skull is, if anything, below that of the ordinary Parisian, but while the average weight of the lower jaw in the latter is about 80 grammes, it is about 94 grammes among murderers. In this respect the criminal resembles the savage and the prehistoric man; among the insane the jaw weighs rather less than the normal average. A type of receding chin is also found frequently among petty criminals, the occasional or habitual, who are criminals by weakness; such heads Lauvergne called têtes moutonnes.
Prominence of the zigoma or cheek-bone has been noted by many observers, especially in sexual offenders, among whom Marro found it in 30 per cent. as against 22 per cent. in normal persons. This recalls a remark made many years ago by Charles Kingsley: “I have generally seen with strong animal passion a tendency to high cheek-bone;” but he confines this generalisation to women, and to those who are dark-complexioned. Virchow believes that the large development of the jaws and the cheek-bones (to which powerful muscles are attached) is favoured by coarse and hard food through many generations.
A few isolated observations have been made on the teeth of criminals by Lombroso, Zuccarelli, and others, who have observed certain anomalies, such as exaggerated or deficient development of the canines; and Dr. Prascovia Tarnowskaia, in her one hundred women thieves, found defects of the bony palate and undeveloped teeth among the most frequent anomalies. So far as I know, however, no extensive and careful series of observations has yet been made on the teeth of criminals. It is desirable that this should be done. The course of dental evolution among the higher mammals is now fairly well known. Atavism in dental anomalies is well recognised among the races of man; a fourth molar, for instance, found generally among the platyrhine apes, is occasionally found in man: in what proportion is it found among criminals? What, again, is the relative condition of the canine teeth? The wisdom-teeth are dying out; they are only absent among lower races in 19 per cent. cases, while in the higher races they are absent in 42 per cent. of the observed cases (Mantegazza). How do criminals stand in this respect? The development of the teeth is very closely related to the development of the nerves and brain. The extraordinary frequency of dental and palatal anomalies in idiots was pointed out in England in 1860 by Ballard and Langdon Down, and they have been carefully studied of recent years by Dr. Talbot, of Chicago, and by Dr. Alice Sollier at the Bicêtre in Paris. It is worth noting, in reference to the undeveloped teeth so frequently found by Dr. Tarnowskaia among women thieves, that Dr. Sollier found abnormally small teeth in 13 per cent. of her idiots. Among the insane dental anomalies are comparatively rare.
