1881.] STUDIES IN COMPARATIVE PHRENOLOGY. 67 STUDIES IN COMPARATIVE PHRENOLOGY. CHAPTER VIII.-(CONTINUED.) DEVELOPMENT OF THE BRAIN IN MAN, ANIMALS, ETC. NOTHING in the whole realm of ther see by consulting the skull cap of a physics possesses more attraction for the student than observation of the gradual development of the organs of the brain in connection with the unfolding A al B A B Fig. 231.-SKULL CAP OF CAT TWO WEEKS OLD. activities and faculties of the mind. The student of physiology who neglects this can scarcely estimate the instruction and pleasure of which he deprives himself. If we take as an illustration the early stages of the cat's brain, we find as the conclusion of many observations* that the convolution in which the propensity to destroy lies, is so moderately developed at birth that the skull cap presents about as much extent anteriorly as in its middle region. At the period when young cats begin to receive from their mother small animals which they have caught for them to eat, and when young dogs begin to gnaw, the mid-lateral parts increase in a striking manner. Figs. 231, 232, represent two skull caps of young cats, one two weeks old, the other four. The parallel lines drawn upon their respective margins show a marked contrast. In Fig. 231 the skull cap is inclosed by the lines; in Fig. 232 its margins at the mid-lateral region, a, a, extend beyond the lines. This region, as we shall fur Dr. Vimont alone watched the development of twenty cats from the moment of their.birth to the third week, and then compared their brains with the cranial indications. cat six months old and one full grown, increase in extent with time. In the adult the mid-lateral regions project greatly, while in the young cat they show but a moderate expansion in contrast. The same tendency of growth is noticeable in those cerebral parts which give to these animals the faculties of place, of cunning, and artifice, so that they can surprise their prey; of watchfulness, so that they are vigilant against danger. In fine, the whole basilar region which is related to self-preservation is marked by rapid development - particularly in the feline and canine families. Quadrupeds with convoluted brains, as they grow old, experience changes in volume and consistency of nervous tissue, which are analogous to those occurring in the human brain. In old horses, old dogs, and old cats the two cerebral substances usually show more. solidity; especially is this the case with the white or fibrous matter. There is often a marked alteration in the hues of the two substances in old horses, and nution. Those who have much to do with horses know that in advanced age their heads show a contracted, wasted appearance in the parts over the eyes. Adhesions of the arachnoidal membrane to the brain are very common in aged horses. Generally the changes in consistence and volume of brain in animals are accompanied with exterior signs which are easily perceived. Horses in advanced age lose suppleness of movement; dogs become more sleepy, and almost always, as it is commonly said, are crusty or snarling. Some species of apes which are very docile in their youth, become incorrigible and very vicious. The loss of facility in movement is coincident very often with softening of the spinal marrow; the diminution in intelligence and docility with the shrinking of the convolutions occupying the anterior region of the cerebrum. Observation of the habits and conduct of apes, dogs, horses, and pigs have confirmed this statement. As regards the pig it should be said that he is by no means as stupid as most people think. The attempt to train him has resulted in phenomena of a surprising nature; but it would appear that whatever instruction is imparted to the pig, is not retained long, for after attaining maturity, the anterior lobes of the cerebrum remain but year or so in full development, and then begin to decrease in vol ume. of dogs and cats. In the herbivoræ, specially the horse, ass, cow, goat, sheep, deer, from two to four years are requisite ere the brain reaches its highest development. Man, however, of all animals, is slowest to come to the climax of nervous growth. 3. In all vertebrate animals the parts situated at the base of the brain indicate earliest development. In some species, particularly in birds and rodents, the spinal marrow and geminal tubercles partake of this early maturity. 4. In the whole series of animals whose brains are provided with convolutions, these are at birth distinctly traceable. But after a time, which varies according to class, order, genus, and species, they are more pronounced, and their development coincides with the activity and breadth of the intellectual and affective faculties of the respective animals. 5. The family of animals whose brains are provided with convolutions, is that in which the most changes in cerebro-spinal organization occur as the effect of age. CHAPTER IX. DISEASED HEADS AND THEIR CHARACTERISTICS. THE history of lesions of the brain, and of its envelopements, merits the attention of those who study cerebral physiology, for in possessing a knowledge of the al To recapitulate the points which have terations of structure wrought by disease, been discussed in this chapter: 1. All the vertebrates, without exception, are provided with a nervous system, situated in the skull and vertebral column. This system is composed of three distinct parts: (1), That related to the intellectual and affectional faculties. (2). That related to the sensory organs. (3). That controlling the mechanical move ments. 2. Birds and gnawing animals develop most rapidly in cerebro-spinal structure. Next follow the carnivora. From eighteen to twenty months are necessary for the complete maturity of the nervous system we are enabled to take definite account of the different phenomena or changes presented by the intellectual or affectional faculties in persons who are abnormally affected. Such knowledge enables us to understand also how craniologists may be led into error in the application of their rules if they do not take into account the pathological condition of the heads submitted to their examination. LESIONS OF THE SKULL. All lesions of the skull may be reduced to three classes: 1. Abnormality of form or configuration. 2. An excess or defi 1881.] STUDIES IN COMPARATIVE PHRENOLOGY. ciency of the calcareous matter entering into the composition of the bones. 3. An increase in the number of the bones composing the skull. To the first class belong all the vices of conformation known under the name of monstrosities. We shall cite as examples of these the two kinds which appear to be more intimately related than others to the history of the development of the skull and the brain. One consists in a sort of atrophy of the cranial bones corresponding with that of the cerebral hemispheres (Fig. 233). This is designated commonly under the term Acephalic, from the Greek word kephale (head) and a privative, and signifying headless-an expression not strictly accurate, since it could be ap 69 were named Acephalic on the ground that they might as well be destitute of a head altogether. The other kind of lesion is quite op plicable exactly to beings only Fig. 233.-ACEPHALIC OR BRAINLESS CHILD, Two-thirds Nat which come into the world entirely without heads. We will presume, however, to infer that as such monsters are entirely or almost lacking in brain, they URAL SIZE. posed to the one just described; it consists in an effusion of watery matter in the ventricles and membranes, and is properly termed hydrocephalus. The result of this effusion is an increase of cerebral volume, the distension causing the channels between the convolutions in some cases to disappear. The bones of the cranium yielding to the pressure of the distended hemispheres separate, and the head may swell to a prodigious size. Hydrocephalic cases are on record, the volume of the heads measuring over thirty inches in circumference. Such a one was that of James Cardinal, who died in Guy's Hospital, London, in 1825, at thirty years of age. His head measured Much more frequent in occurrence than the hydrocephalic form of abnormality is that defective condition of the anterior lobes of the brain which is known as Idiocy. According to the diminution of the cerebral volume, is the degree of the mental weakness. As the result of hundreds of observations, it may be stated as a general rule, that a head which measures less than seventeen inches in circumference is lacking in that integrity of cerebral function which constitutes a person a useful, intelligent, self-supporting member of society. There thirty-three inches in circumference, and | are many persons with small heads who was found to contain five quarts of water. He was intelligent and clear-minded in spite of the disease-a condition which is of very rare occurrence in connection with hydrocephalus. Generally the pressure exerted by the effusion suppresses the organic action, so that the faculties of sense or thought are more or less impaired. In almost all cases sight is imperfect; some have attacks of somnolence more or less prolonged: some can not endure the least noise; and frequently paralysis of the lower limbs accompanies the disease. show remarkable talent in some mechanical direction, and under the control of others are made useful, but they are incapable of exercising their intellectual faculties in a coherent and practical manner. Figs. 234 and 235 represent heads in which the degree of imbecility is strongly contrasted. Fig. 234 is that of a girl twenty-three years of age-a complete idiot, incapable of providing for her personal wants in the least. Fig. 235 belongs to the class of partial idiots, or, as they are now usually termed, feebleminded persons. The difference in the 1881.] THE SELFISH FEELINGS OR PROPENSITIES. form of this head from Fig. 234, especially in the anterior lobes, is very marked, while its size was much superior. It must be admitted here that we sometimes meet with men and women whose heads are very small, barely exceeding eighteen or nineteen inches in circumference, and who nevertheless exhibit striking intelligence, in special directions. But this, so far as our observations have extended, is always due to the fact that the cerebral organs, in which the intellectual faculties reside, are well-developed, while the parts belonging to the emotional or sentimental faculties are very small. In such a case a person may possess a high degree of the observing and reflective organs, and his head 71 may be high at the crown without showing a large circumference. On the other hand a head may measure considerably more than the average in circumference, because the organs of the propensities and affections, at the base of the brain, are very large, yet be wanting greatly in intellect and moral sentiment. The Cretins of the Alps offer a suitable illustration of this type of development, and so also do criminals of the most debased type. It must be remembered that the bones of the skull associated with low types of cerebral organism are usually thick, and their prominences at the supra-orbital ridge and mastoid process, etc., are more conspicuous. (To be continued). D. THESE THE SELFISH FEELINGS OR PROPENSITIES. HESE are related to the lower lat- | a physico-mental organization; he is nateral region of the head, a space which may be described as a semicircle whose center is in the ear. When the organism here is largely developed, the base of the head is wide and prominent; and if the selfish instincts dominate in the mental character, the head from the ear upward, when observed in front, has a pyramidal contour. While a good degree of these instincts is essential to mental integrity, as they lead one to provide for his physical wants, to protect himself and property against wrong and robbery, their excessive influence is destructive to the mental balance, and may lead to vice and crime. They who break the laws of order and propriety often, they who are found in the grated prison, are, as a class, largely developed in the lower side-head. Destructiveness, Combativeness, Secretiveness, Acquisitiveness, Appetite, when active give energy, strength, vigor, and efficiency to man; but unless restrained by the moral sense and directed by the Intellect they become elements of disorder and perversion. The child with a large base of brain in the intellectual, social, and propensitive regions is endowed with what is termed urally strong and robust in body, fond of exercise and everything related to muscular movement. His appetite is vigorous and needs government; his temper is easily aroused, and stormy. He is impatient of restraint, and liable to commit improprieties under the influence of passionate impulse. He is "a difficult subject" to manage, and taxes the intelligence and kindness of parents and teachers in their effort to train him in ways of order and decorum. In school particularly does he try the patience of a teacher, for he has little aptitude for the study of books, and chafes under the confinement of desk and bench. His vigorous limbs demand free play; he would be abroad in the free air of field and forest; the outer world affords him the school of his choice as it furnishes employment for his sturdy muscles and coarse nervous fiber. Such as he are well constituted to perform the world's strong work; to build the bridges, railways, steamships, highways, to clear the forests, level the mountains, fill the valleys, and perform the other grand services demanded by an advancing civilization.—From “Indications of Char acter." |