1. The carpus and tarsus are subject to the same types of anomalous development.

2. Congenital anomalies may or may not be hereditary; they may be bilateral or unilateral; and they may undergo pathological changes.

3. Teratological data are commonly misused for the fabrication of unsubstantiated phylogenetic speculations.

4. Four types of anomalies must be distinguished: (a) extensive abnormalities; (b) fusions; (c) accessoria; (d) bipartitions.

5. Carpal absences are usual in the "paraxial hemimelias". Duplications and absences are found in polymelic conditions (double foetus, symmelia, partial limb duplication).

6. Congenital carpal or tarsal fusions may occur between almost any two elements, and probably arise as an absence of joint cavitation, and chondrification of the embryonic "interzone". Lunatotriquetral fusion is the most frequent type in the hand; its relation to an accessory ossicle seems to be gratuitous. "Peroneal spastic flat-foot" is generally due to talocalcaneal or calcaneonavicular fusion.

7. Many accessory ossicles have been described a number have been found in the embryo. Postnatal pathological origins in some instances must also be kept in mind, however. It is not practicable at present to distinguish "accessory" from "sesamoid" bones. Many accessory bones exhibit "bilocation", that is, they may occur either at or as a process on one of the major elements. It is suggested that the terminology of the accessoria be standardized in agreement with current anatomical nomenclature.

8. Although most divisions of bones are traumatic in origin, a few cases seem to be congenital. Bipartite scaphoid probably arises from two mesenchymal or cartilaginous centers, and the division is at the waist. Bipartite medial cuneiform is divided into dorsal and plantar parts. Endocrine factors may be operative in some cases of bipartition, as in hypothyroid epiphyseal dysgenesis, characterized by multiple ossific foci.