Pedagogical Anthropology

by Maria Montessori

The two halves must be made to coincide in such a manner as to reproduce faithfully the thoracic section, both in form and in dimension.

By adding up the squares contained within the outline we obtain the area of the section.

Fig. 126.

This method is the only really rational method for studying the thorax; and its simplicity, practicality and graphic representation recommend it as a valuable aid to pedagogic anthropology.

There is, for example, an abnormal form of thorax, which I have very often met with in deficient children. It consists in an exaggerated curve of the posterior costal arches, which consequently form a very sharp angle with the vertebral column, which is notably indented, while the sternum is also depressed in a groove, and occupies a plane posterior to that of the ribs. The section of the thorax, in this case, approaches the form of a figure 8; and the thoracic perimeter would not represent the true measurement because it would include the empty spaces left by the front and back depressions. The thoracic index would also give a false idea of the facts, because the antero-posterior diameter would be nowhere so short as at the centres of measurement for this diameter.

The only method for representing the true shape and area of this type of thorax is that employed by Maurel.

Anomalies of Shape.—In addition to the preceding anomaly, very frequent in degenerates, and associated with a deficient development of the lungs and with physical weakness, there are numerous other anomalies. Among others, those that principally deserve attention are the funnel-shaped or consumptive thorax, in which the longitudinal diameter is excessive; the thoracic frame is greatly elongated and the ribs descend to a very low level; this type of thorax is frequent in neuropathic women, and, according to Féré, is associated with degeneration.

The opposite form is the barrel-shaped thorax, in which the prevailing diameter is the antero-posterior; it is very prominent and is frequently met with in persons who are subject to forms of asthma, maladies of the heart, etc.

The bell-shaped thorax is similar to the preceding, but is characterised by an accompanying exceptional brevity of the longitudinal diameter, which causes it to resemble the infantile thorax (arrest of morphological development).