18 OF THE PELVIS. 



such a view of it, it does not follow that we ought to do so in toko- 

 logy. The accoucheur must necessarily study the pelvis as a por- 

 tion distinct from, and, as far as connected with his art, independent 

 of the rest of the body. Hence it is, that all authors since the time 

 of Smellie and Levret have followed this course; which I shall ac- 

 cordingly adopt. 



SECTION 1. 

 Of the Bones of the Pelvis. 



2. There are four bones in the adult pelvis: the sacrum and coc- 

 cyx posteriorly, and on the median line; and the coxal bones in front, 

 and on the sides. As he who is destined to engage in the practice 

 of midwifery ought to be made acquainted with the entire pelvis, I 

 do not deem it necessary to dwell at length upon the graphic details 

 that are to be found in most of the classical works upon each con- 

 stituent portion of it. On this subject there exists, even in our most 

 modern works, quite a faulty mode of exposition, which it is proper 

 to reform: after the manner of Baudelocque, the pubis, the ilium 

 and ischium are minutely described as so many separate bones, 

 while, for the most part, the coxal bone is almost entirely lost sight 

 of; and yet it alone possesses any considerable interest in relation 

 to midwifery, inasmuch as the three pieces of which it is composed 

 are united into one before the individual is liable to become preg- 

 nant. 



§. I. Of the Sacrum {os sacrum, s. clunium). 



3. The sacrum, a single bone, situated between the last lumbar 

 vertebra and the coccyx, is locked in, as it were, between the two 

 ossa ilia. 



4. Of a triangular or pyramidal shape, curved forwards on its an- 

 terior surface, it presents to the examiner, successively, an internal 

 or pelvic region, and external or posterior region, two edges, a base 

 and an apex. 



5. Its anterior surface, somewhat concave, presents, 1. Along its 

 middle, four or five quadrangular facettes, and the same number of 

 transverse lines; 2. Outwardly, the five anterior sacral holes, ter- 

 minating in an equal number of converging grooves, for the passage 

 of the anterior branches of the sacral nerves; 3. More outwardly 

 still, and between these openings, certain rough, uneven surfaces, 

 for the attachment of the pyramidal muscles. 



6. Its posterior surface, which is convex and very uneven, exhi- 



