The Authors have studied radiographically the thorax of 11 pairs of uniovular twins and of 16 pairs of binovular twins. They have performed and analyzed the standard radiographics of the thorax as well as four transverse laminagrams. The results show a greater concordance of the cardio-vascular shadow and that of the pulmonary hili in the uniovular twins. This concordance is more marked and demonstrative in the transverse laminagrams than in the standard radiography. The Authors think that this finding is due to a lower incidence of the functional variants in transverse laminagrams. Moreover, they have given the name of lingua pectoralis to a peculiar radiographic image of the anterior mediastinus.

Report about the many possibilities of pathological dwarfism. It is not too much if we suppose, that more than 100 different gens may cause special forms of pathological dwarfism in man.

A mathematical model is described, covering the case of paired recessive diallelomorphs with different degree of penetrance in the pairlings, according to whether the proband carries 1) the trait, 2) the genotype but not the trait, 3) neither the genotype nor the trait. The incidences of trait-carrying pairlings in the three proband groups are expressed in terms of population genetics and formulae given, together with some conclusions.

The Author studies the relations between the physical and psychical resemblances in two groups of similar (18 pairs) and dissimilar (21 pairs) twins.

The physical characters considered are: the measurements and indexes of the head, face and nose.

The psychical characters are: attention, auditive memory, visual memory, taste for colours and mental level.

The similar twins betray great resemblance with regard to the measurements and indexes of the head and face and very notable differences with those of the dissimilar twins (excepting the measurements and indexes of the nose).

With regard to the psychical characters studied, many (visual memory, taste for colours, mental level, concordance in mistakes) do not show any notable differences. The auditive memory (weak) and the index of attention (very high) betray, however, notable differences. No correlation is observed between physical resemblance (given in millimetres) and concordance in mistakes; while the relation is strong between physical resemblance and the index of attention.

The Author sets out his standpoint on the value concerning the « forme fruste » of syndromes of multiple malformations expecially of those which have hereditary nature. He remembers the four types of « mandibulo - facial dysostosis ». The Author describes a family in which the different members were affected by this illness in incomplete form. In the last generation by two parents having the « forma frusta », two children were born, affected by a complete Mandibulo - facial Dysostosis both after having lived two or three months. After a close examination of medical literature referring the familiar forms, man examine all the genetical eventuality concerning the examined family. Man can reach to a conclusion that the appearence of two brothers with a complete forme, precociously dead, is quite surely imputable to « homozygotism » and consequently to double close of « pathological genes ».

On the ground of an inquiry, carried out on pedigrees of 74 patients with arthrosis, clinically evident, the AA. found evidence of a genetic predisposition to arthrosis.

On a total number of 809 membres, excluding the proband, of these families, they found in 20,8% of them, painful arthrosis, while in 100 families, taken as controll, this percentage is 5,5.

The genetic predisposition to « painful arthrosis » is trasmitted as a dominant character with the parents condition of ge 65,2%), warying according with reduced penetrance (averahaving or not having this disease. There is no avidence, according with the statistical data obtained, of a common genetic ground of predisposition to painful arthrosis and to the two main Rheumatisms (Rheumatic Fever and Rheumatoid Arthritis).