by its three upper segments, and by them only, the two bones, sacrum and innominatum, there indent each other mutually and thus give rise to an ear-shaped joint-surface, which is called the auricular facette, in each of them. This auricular facette has, therefore, nothing to do with the fourth and fifth segments of the sacrum, for they nowhere touch the innominata, but are separated from them by the incisura, deep cut, or sacro-sciatic notch.

If, in any sacrum, the wings are correctly developed, the superior strait cannot be deformed in such a way as to produce what is called the oblique ovate pelvis, for the curve or round of the linea ilio-pectinea must be, in such case, correctly drawn; but if one of the wings, which ought to be about fourteen-tenths of an inch, should be only five-tenths of an inch long, the pelvis must of necessity be deformed or crooked, having the pubal symphysis cast far over to the right if the fault is in the left, and far over to the left of the mesial line if the right wing is too short.

Fig. 10.

As the concavity of the wing determines the shape of the inner wall of the pelvis there, it is evident that too short a wing will cause the change of form above mentioned, and determine the existence of the oblique ovate deformity. I should think this too evident to require any further illustration than that of the subjoined Fig. 10, which is a camera-lucida drawing from an oblique

ovate pelvis in my museum at Jefferson College. The left wing is seen to be the contracted or faulty one, whose shortness has caused the symphysis pubis to be placed awry, or far over to the right. The fault is connected with a bony anchylosis of the left sacro-iliac synchondrosis— a circumstance common in these ablique ovate deformities.

Great attention has, of late years, been paid to the influence of the sacrum in producing horizontal deviations of form in the pelvis, and our modern information on the subject is principally due to the care of the late eminent Prof. Naegelé, of Heidelberg, in giving to us his work Das Schraag Verengtes Beckens. Dr. E. Gurlt, also, in his Ueber

Einige durch Erkrankung der Gelenksverbindungen Verursachte Misstaltungen des Menschlichen Beckens, furnishes us with copious notices of what has been done for our science in this particular up to a late date. While it is to Dr. Anton. F. Hohl, in his Zur Pathologie des Beckens, 4to., 1852, that we are indebted for the fullest and clearest accounts of the matter of oblique oval deformations. Prof. Rokitansky's 3d vol., Manual of Path. Anat., p. 250, furnishes that teacher's views of the deformity, which he attributes, in some cases, to congenital, and in those that occur after birth, to rachitic causes; as does also Scanzoni, p. 149, Lehrbuch der Geburtshilfe, 11 Band. For the present it may suffice for the student to reflect that faults in the wings of the sacrum cannot but bring about great faults of form in the female pelvis-the nature of which he will, from the foregoing, readily comprehend.

I beg the student to examine the ten holes called sacral foramina, which he will find in the front or hollow of the sacrum (Fig. 8), that he may inspect the grooves there to be seen. As those holes give passage to large nervous cords that go to make up the right and left sciatics, let him notice, in these grooves of the sacral foramina, provision against dangerous pressure and contusion of those important nerves by the passing head of the child. Even with the protection. of those grooves, serving, as it were, half to bury or hide the nerves in their hollows, few women having labor pains fail in some one of the stages of parturition to admit of a severe pressure of the nervous cords, and when the hard bony head of the foetus is jammed with considerable force upon the sensitive substance, the laborant is heard to cry out that she has cramp in the thigh, or the leg, or the foot. For a woman in labor, the natural labor pains are as much as she can well bear; and she can bear them well if she be of a firm courage and blessed with patience and hope; but if some abnormal and extrinsical pain comes to attack her, the course of nature seems to be turned aside or prevented, and the labor stops. Hence it is that a severe pressure on one or more of these sacral nerves, may wholly arrest the progress of a child-birth, and eventually compel the practitioner to interfere by means of instruments.

I think one of the most fearful instances of human agony that my eyes have ever witnessed, was that of a lady in North Sixth Street, Mrs. Th. Sy, who, being in labor of her first child, and making rapid progress towards a delivery, began suddenly to scream, with the greatest violence, often uttering the words, "Oh, the cramp! the cramp! the cramp!" She was indescribably agitated, her countenance assumed the wildest expression, and all the persons in her chamber became much alarmed on account of the extreme degree of anguish, or rather

agony, which was depicted in her countenance and expressed by her shrieks. I had, for many years, been accustomed to the cries of puerperal women, to which I had become habitually indifferent, but this case deserved to be called terrible. The cramp affected the muscles of her right leg. I explained to her that the cramp was caused by the pressure of the child's head upon one of the right sacral nerves, and though the appearance of the case was appalling, I exhorted her to bear down, hoping a few vigorous efforts would push the head lower than the point of pressure and relieve her from the misery. I was disappointed: the cries ceased with the relaxation of the throe, only to return with every renewal of the contraction. So intense was her distress, that she began soon to show signs of exhaustion of nerve-force, and I have now no doubt that she was in imminent danger of death from the excess of pain. The labor, as to its progress, was arrested with every renewal of the labor-pains; and it appeared that her whole life-force and perceptions were occupied with that sole agony. I was three-fourths of a mile from home; and while her husband was gone for my forceps, for which I immediately sent him, she renewed her cries about every four minutes. I think she would have died in half an hour. Upon receiving the instrument, I speedily applied it and drew the head below the compressed point, and she bore the extraction of it without a murmur, for the nerve was set at liberty as soon as I had drawn the head below it. During more than a fortnight after the labor, there was a partial paralysis of the limb, following the pinch the nerve had suffered betwixt the fœtal head and the bony pelvis. It did not wholly disappear for many days. Two years later I encountered a similar scene in the same. apartment. She seemed to dread nothing in the approaching labor. but the "cramp!" and engaged me to be prepared with my forceps, which I unfortunately declined to do. When the head descended into the pelvis, she was seized with precisely the same kind and degree of pain; the forceps were brought to me from the same distance, and she was again as speedily relieved. In this labor, as in the former, a partial paralysis and numbness of the leg followed the parturition, and did not disappear until the month was out.

In a third labor, during which I was confined to my house by sickness, she came under the care of my able colleague, Dr. R. M. Huston, well known for his skill as an obstetrician. The same scene was renewed in this third case, and the Doctor felt obliged to relieve her by extracting the head with the forceps. I have attended her in a sixth labor in the year 1846, and in a seventh on the 1st November, 1852, in which the position of the child was such as to avoid the pressure,

and she gave birth to the infant without cramp, or any uncommon pain.

I was in attendance upon a lady living in Turner's Lane, two and a half miles from my house. The labor had proceeded very towardly until the head got well down into the pelvis. I was in a lower parlor conversing with her husband when we were both startled by the sudden, sharp screams of the patient from her chamber in the second story. We both hastened to the apartment, where I recognized a scene in all respects like those witnessed in the accouchement of Mrs. Sy. After vainly exhorting my patient to bear down and push the child lower than the nerve, I engaged Mr. to wake his servant, for it was night, and send him on the fastest horse to the city for my forceps. Her agony was indescribable during the whole period of his absence. He had a ride of five miles-out and in. I got the instru ment, and the child was delivered within two or three minutes after it was placed in my hands. No evil consequences followed the pressure in this case. She had had several children, but in none of the labors had the nerve got so severe a pinch. Here, then, are six cases of forceps operations rendered indispensable by pressure on the sacral nerves. I have seen no accounts

many hundred

of similar instances in the books. I have met with labors in which cramp was more or less violent; but these cases, above mentioned, were really frightful, and I have no doubt that both the distress and the danger were sufficient warrants for the instrumental assistance.

Very violent cramp in the leg or thigh sometimes attends upon awkward attempts to introduce the forceps, because the ignorant or careless operator suffers the end of the blade to press upon one of these sacral nerves, as it emerges from its foramen and passes along its groove. Any one who is causing this pain with his ignorantly directed instrument is, at the same time, in imminent danger of tearing open the thin postero-lateral wall of the vagina, and plunging the point of the clamp into the sack of the peritoneum; let him tremble for his rashness, and instantly desist from so wrongful a proceeding. While the forceps is passing upwards, the chamber should be kept very still, no one being allowed to talk, so that the operator may immediately know, by the woman's expressions or silence, that the blade is passing in the right direction.

Os Coccygis.-I here present a figure that represents the terminal or caudal extremity of the spinal column, of the natural size. It is called the os coccygis or cuckoo-bone, in vulgar language the crupper

bone. It consists of three pieces, altogether about an inch and a half long, that are separable in the young, but become anchylosed into one solid piece as advance is made in years. Two styloid processes ascend from the posterior lateral surfaces to rest upon the back part of the apex of the sacrum, and prevent the point of the coccyx from being driven too far backwards by the displacing pressure of the fœtus in labor. The cornua, however, are not strong enough always to resist, and they occasionally break off with a loud sound. The sound may be heard at the distance of many feet from the woman in travail. In general, no very great inconvenience is produced by this fracture; although there are met with some instances in which a long-continued pain follows the accident.

In young women, the articulation of the coccyx and sacrum is a movable one; anchylosis takes place only in those who begin to grow old, in advancing beyond the youthful season of bloom and beauty. Hence, it is better that a

Fig. 11.

woman should have her first child before this bony anchylosis takes place, inasmuch as, when the sacrum and coccyx have become immovably joined together, the point of the little bone may arrest or distressingly retard the acts of childbirth.

The movableness of the coccyx upon the sacrum is much relied upon as a means of amplifying the antero-posterior diameter of the lower strait of the pelvis; but I do not think that the point of the coccyx usually recedes much during the transit of the foetal head in parturition. Though most writers attribute to the coccyx a power to recede very considerably, my own observation has led me to regard this recession as less than it is generally reputed to be, and inspection confirms this doubt. The point cannot go very far backwards but at the expense of a fracture of the cornua and of the lesser sacro-sciatic ligaments, which tie it firmly in a certain proximity to the tuberosities of the ischia.

The Os Innominatum.-The side bones, which are technically known as the ossa innominata, or nameless bones; and also ossa coxalia, or hip-bones, by touching each other in front, and by resting at their posterior extremities upon the wings of the sacrum, serve to complete the whole pelvis, except the small os coccygis at the apex of the sacrum, which has been already described.

An os innominatum is so irregular in its shape, that I do not think