sagittal suture existed, that they were not directly continuous with each other, but that the sagittal joined the coronal, in some a little to the right, in others a little to the left of the frontal suture. How far this difference in the rate of ossification of a bone or bones on one side, over its, or their, corresponding one on the opposite side may be assisted, or retarded, by unilateral pressure, set up by a persistent adherence to any unvarying position in suckling and nursing, such as Professor Daniel Wilson suggests,* acts as a not unfrequent cause of cranial distortion, may be reserved for future consideration and inquiry.

cause one region to Thus, for example, centre, proceeds at

Again, this difference in the rate of ossific formation may also take place on both sides of the skull, so as to preponderate over and to infringe upon others. if the ossification of the parietal region from its a greater rate than that of the frontal, occipital and squamous regions from their centres, then would the areas of these last named be infringed on, and the parietal bones would constitute a larger portion of the sides of the skull than would otherwise have been the case. The direction of the coronal, lambdoidal and squamous sutures would be by this process at the same time affected. It is to this lack of symmetry on the two sides of the head, slight though it may be, and to the variations in the amount in which one region preponderates over another, that those characters which constitute individual and ethnical differences, in some measure consist.

But a far more important cause of cranial distortion, and one which produces much more aberrant forms, is the premature union of adjacent bones along their sutural margins, and at their synchondroses. Of the cranial synchondroses by far the most important, is that which exists at the basis cranii between the basilar processes of the occipital and sphenoid bones. So long as it remains unossified, and this it generally does, until or somewhat beyond the age of puberty, the growth of the skull in the antero-posterior direction is permitted. Should this become ossified either before or shortly after birth, as Virchow has shown to be the case in the skulls of Cretins, then not only is the growth of the cranium in this direction interfered with, but deformities of the vertex and sides may be occasioned. But the distortions of these last-named parts are more

·

* Canadian Journal, vol. ii. p. 406. Ethnical forms and undesigned artificial distortions of the human cranium,' p. 16. Also Gosse, Essai sur les deformations artificielles du Crane,' and Dr. J. B. Davis in Crania Britannica,' Decade 1, p. 42.

frequently due to a premature ossification of one or more of the sutures on the summit and sides, and it is of these I shall now speak.*

It will be convenient that we should, in the first place, attempt a classification of these sutures. They naturally arrange themselves into four groups, a vertical transverse, a median longitudinal and two lateral longitudinal.

The vertical transverse consists of the coronal and lambdoidal, the sphenoido-malar, the sphenoido-squamous and the occipitomastoid sutures.

The lateral longitudinal consists on each side of the fronto-nasal, fronto-maxillary, fronto-ethmoidal, fronto-malar, fronto-sphenoidal, parieto-sphenoidal, parieto-squamous, and parieto-mastoid sutures.

Both before and for some time after birth, the bones of the skull grow in a direction perpendicular to the lines of these different sutures. By their growth in a direction perpendicular to the vertical transverse sutures, the skull increases in length; in the direction perpendicular to the median longitudinal it increases in breadth; whilst by growth perpendicular to the lateral longitudinal sutures it increases in height. Should therefore a premature ossification, either before or shortly after birth take place in one, or more than one, of the whole, or a part of a line of sutures, then necessarily the growth of the skull corresponding to, and in a direction perpendicular to the line of synostosis will occur, and diminished length, or breadth, or height, as the case may be, will be occasioned, This proposition is one of great importance in connexion with all these varieties of cranial deformity, and for the first clear enunciation of it, we are indebted to Professor Virchow.t

To render more clear the principle contained in this proposition, it may be well for us to employ in illustration, some examples of malformed crania. With this object, I have more especially selected, from several distorted skulls, which have come under my observation, the remarkably elongated and laterally compressed crania, to which I now direct the attention of the Section. And in my description, I shall adopt the term, which has been proposed by the distinguished

The importance of these sutures, and of those at the base also, in relation to the normal growth of the skull, and the increase in size of its cavity, is fully recognized by Professor Meyer. His account is given, at p. 68, of his 'Lehrbuch der Physiologischen Anatomie.' Leipzig, 1856.

Gesammelte Abhandlungen,' p. 936.

ethnologist, Professor von Baer of St. Petersburgh, and speak of them as Scaphocephalic crania. Of this peculiar form of cranium, I have examined four as yet undescribed specimens, two skulls, a skull-cap, and a cast. And, in addition, I am acquainted with a member of my own profession, a native of Scotland, who undoubtedly possesses a skull of this peculiar form.

Of the skulls, skull-cap, and cast, I append the following description.

1. Two years ago, the body of a very powerful adult man was brought to the dissecting rooms of the University. He was found dead on the beach at Newhaven, and had evidently been some time in the water, for he was green and otherwise decomposed, and his face was much injured. He was conjectured to have been the carpenter of a ship, who had been drowned in the Firth of Forth, a short time previously. To all appearance, he was a native of Western, or North Western Europe. The peculiarly elongated shape of his head, at once attracted attention, and the skull was preserved for more careful examination. It is now placed in the Museum of the University of Edinburgh, No. 117, a. Skull of a singularly elongated form. Laterally compressed. Sagittal suture obliterated, its line marked towards the posterior part, and in the middle of the region by a ridge which quite disappeared anteriorly, where the bi-parietal bone ran forward into the frontal bone, and formed a sort of beak, which evidently occupied the region of the anterior fontanelle. The sides of the beak were bounded by the coronal suture, which was in consequence pushed forward at this spot. Traces of a suture might be seen in the bi-parietal bone commencing in the coronal suture immediately to the right of the base of the beak, and extending backwards and inwards for about ths of an inch towards the middle line. Right parietal foramen small yet pervious, left obliterated, but its original position indicated by a depression. There were

I have adopted the term Scaphocephalic, because it expresses most clearly the peculiar boat-shaped form which these malformed crania possess, and because it is desirable, I think, that they should have a distinctive appellation, one not to be confounded with terms which have been applied to express ethnical characteristics. Thus the term kumbo-cephalic, proposed by Dr. Daniel Wilson, to express a boat-shaped skull ought, I would submit, to be restricted to those crania in which there is no evidence that the characteristic shape is due to a premature synostosis. It will be better again to restrict the term macrocephalic to such crania as have a shape similar to the Crimean Macrocephali. The term dolico-cephalic, given by Virchow, to these elongated crania, has been now so long employed as a distinguishing name for the long-headed races, that, as an expression of the peculiar shape of these crania, it has lost all significance.

some faintly marked elevations and depressions, scattered over the posterior part of the bi-parietal bone, especially near the sagittal ridge, but they never assumed a radiated appearance. The groove for the superior longitudinal sinus was well marked, and corresponded internally, to the sagittal ridge externally. The coronal suture was well marked externally; but obliterated internally. The frontal suture well marked externally, but obliterated internally. The persistent frontal suture, is a quite exceptional character in this specimen. It has not been described or figured in any other recorded skull possessing this peculiar shape. The lambdoidal suture well marked with long irregular teeth externally, obliterated internally. The squamoso-parietal and other sutures in the lateral line all distinct and open. Forehead ample, though not so dome-like as in the skull next to be described. Superciliary ridges well marked. Frontal eminences fairly marked. In the anterior, or frontal view of the skull, indications of a roof-like summit could be seen, for the frontal bone sloped away in its upper part laterally from the median frontal suture. Skull laterally compressed in the

* For permission to describe and engrave a figure of this cranium, and of the

ea varium, No. 117, I am indebted to Professor Goodsir.

parietal region. Parietal eminences absent, so that the cranium had a flattened appearance at the sides of the parietal region. Temporal fossa much elongated but shallow, the summit of the temporal ridge, nearly two inches below the sagittal ridge. The backward projection of the skull in the occipital region, was one of its most striking characters, the part of the occipital bone situated above the superior curved line, being as it were bulged out posteriorly, and for the most part directed downwards and backwards. The posterior occipital protuberance, and superior curved line, not very strongly marked, the parts of the bone above and below that line, running into each other, with a gentle curve. Basi-occipito-sphenoid synchondrosis closed. The basilar process formed with the plane of the foramen magnum a very obtuse angle. Projecting into the cranial cavity from the upper surface of this process, was a small, conical exostosis, similar to the one figured by Virchow in Fig. 14, Taf. vi.* and the posterior clinoid processes were very high and arched over the sella turcica. The cavity of the skull, was elongated in the antero-posterior, compressed in the lateral direction. The inner surface of the cranial bones was marked as usual by grooves for the ramifications of the meningeal arteries and depressions for the cerebral convolutions.

II. Cranium from the collection of the late Dr. Barclay, in the Museum of the Royal College of Surgeons of Edinburgh. No. 27. Skull of a singularly elongated form, probably a female; evidently that of a youth, judging from its general appearance, from the teeth being scarcely worn, and from the wisdom teeth being still concealed. Sagittal suture obliterated, no ridge along its line but the parietal bone in its posterior 3rds close to the middle line, was rough externally and pitted with a number of small yet well marked depressions. In the anterior 3rd the bone was quite smooth, and no mark was present to indicate the mesial junction of the right and left bones. No beak extended into the frontal bone. The groove for the superior longitudinal sinus, was but faintly marked, the parietal bone along this line being in places ths of an inch thick. Coronal suture perfect throughout, denticulations long and serrated. Lambdoidal suture on the left side very faintly marked externally, but quite obliterated internally; on the right side, the upper half of the occipital and posterior part of the parietal bones had been removed and lost, so that the condition of this half of the suture could not be ascertained. The

* Entwicklung des Schädel-grundes.'