Following a suggestion of Gedda and Bérard-Magistretti, intra-pair differences between MZ twins in fusional reserves were compared with differences in psychological variables. While the strong relationship between twin leadership and FR which these workers found in twin children was not confirmed in the present small sample of 14 adult pairs, the twin with the higher FR tended to be the more introverted, the more intelligent and the one who volunteered for the investigation. He also tended to be the taller and the first born.

Further studies, including the temporal reliability of scores of fusional convergence, are required before the value of this characteristic as a psychological criterion can be established.

The authors explain 9 cases of Bart's Hb. and one case of Hb. Alexandra, identified on 3.556 blood samples from the umbilical-cord in human newborn in time. Electrophorectical and spectrophotometrical examinations showed that Bart's Hb. is identical to Hb. H2 (the least fast of the two Hb. fractions present into the bearers of Hb. H).

In 7 newborn infants, it has been possible with Bart's Hb. to reexamine them, some months after they were born; it was observed that the said haemoglobins had disappeared; at the same time, in 4 of those subjects, a clear microcytemic picture was noted while in 3 others, still very small, the microcytemic picture appeared still uncertain. In 8 families with newborn babies with Bart's Hb., the two parents were also examined, and in 7 of these families one of the two parents presented a microcytemic picture; in one of them the hematologic traits were normal in both parents, except a very hight alteration of the eritrocyte morphology in the mother.

None of the examined parents presented any abnormal haemoglobin; furthermore, all microcytemic parents (except one) and all children with Bart's Hb. presented a normal rate of Hb. A2. This fact, absolutely similar to that observed in the bearers of Hb. H and in their microcytemic relatives, allow to put forward the hypothesis that Bart's Hb. and Hb. H appear in the same families in which we find that special type of microcytemia without any increase of Hb. A2, which would correspond to the microcytemia of the α chain.

In this work the results of a research on the consanguinity of populations living in the Lodigiano, the southern part of the province of Milan, are exposed and briefly commented.

It has been found:

1) a relatively low incidence of consanguineous marriages from the third to the sixth degree (uncle-niece and aunt-nephew, first cousins, first cousins once removed, second cousins and double relatives), which varies with the time and the number of inhabitants of the «comuni»: in the whole, from a frequency of 2,27% in the years 1900-1923 they have decreased to 1,54%, in the years 1933-1956;

2) correspondently low coefficients of inbreeding, being F 0,00101 in the first period and F 0,00061 in the second;

3) no negative correlation between the number of inhabitants of the «comuni» and the incidence of consanguineous marriages.

The marked difference between these results and that obtained for the other part of the province of Milan shows how great the variability of this phaenomenon is even in small areas; variability that should be accurately evaluated and taken into account for studies of population genetics.