Lineæ albicantes on the abdomen, buttocks, and breasts indicate the female sex, and the probable occurrence of previous pregnancies. It must, however, be remembered that lineæ albicantes occur in males who have been stout or had the abdomen distended by disease.
The Skeleton in Relation to Identification.—When a complete skeleton is submitted for examination, the chief points to elucidate are the age and sex. These will be noted further on. It may happen that a single bone, separate bones, or only a part of one is obtainable, when there may be considerable difficulty in expressing a definite opinion. The questions to be answered are: Are they human or belonging to the lower animals? When the bones are entire the answer is not very difficult to settle; but when parts of bones have to be dealt with, one has to be very careful in forming conclusions, and the fragments may have to be submitted, to a skilled anatomist. One may not be able to express an opinion about bones of the lower animals, other than to state they are not human. The services of a skilled Comparative Osteologist may be necessary to decide the nature of the animal.
When fragments resembling bone have to be examined, the microscope will be necessary to determine their osseous structure. When several bones have to be examined it may be possible to build up part or the whole of a skeleton. Duplicate bones will indicate remains of more than one creature. All fragments and bones should be carefully described, measured, and photographed.
By the character of the bones one may be able to determine the sex to which they belong and the approximate age. As a general rule the bones of the female are smaller, lighter, and less marked by muscular and other attachments.
The thorax in the female is deeper than in the male, the sternum shorter and more convex, the ensiform cartilage thinner and ossified later in life. The cartilages of the ribs are larger and the ribs smaller than in the male. The ribs are more oblique and may show the results of long corset pressure. The body of the sternum is over twice the length of the manubrium in the male, less than this in the female.
The length of the twelfth rib in the male averages 103 mm., in the female 83.8 mm. The pelvis exhibits marked differences. The sacrum of the male is more curved than that of the female, which is straighter in the upper half and more curved in the lower. The male pelvis is more compact, deeper, rougher, and narrower. The pubic angle is smaller, the obturator foramen is oval, and the ischia incurved. The female pelvis is more open, shallower, wider, not so rough, a wider pubic angle, and shallower and broader symphysis, the ischia are everted, wider apart and flatter, and the obturator foramen triangular. The inlet of the female pelvis is greater in all its diameters.
The skull in the male is heavier and larger, the markings and ridges being more pronounced, the mastoid processes, occipital protuberance, zygomatic and superciliary ridges are more prominent, and the capacity greater than in the female.
In the female the jaw is less prominent and has a wider angle.
The lumbar curve is longer in the female, and the lumbo-sacral angle greater than in the male.
The angle made by the neck of the femur with the shaft is about a right angle in the female, more obtuse in the male. It must be remembered that these differences between the sexes are not present to the same degree before puberty, so that prior to it the examination offers little evidence as to sex.