From the whole of genealogical researches on the people of B., P. and Al. towns, we came to the following conclusions:

1) the monomeric recessive autosomal transmission of hydrophtalmos, with a high degree of penetration, has been confirmed;

2) a type of congenital cataract with monomeric recessive autosomal hereditary transmission, with a comparatively reduced degree of penetration, has been located;

3) in towns B. and P. affected lines of hydrophtalmos and congenital cataract have been located;

4) the first definite heterozygotes for hydrophtalmos in town B. and for hydrophtalmos and congenital cataract in town P. have been located: they date back to the first half of the 18th Century;

5) the date of hydiovariation's inception has been located at about two or three generations before, or around the middle of the 17th Century.

The statistics of twin births in Australia and Italy were examined and the frequencies within the two countries at different periods of time compared. There has been an increase in monovular twin frequencies in Australia over a period of 25 years in spite of an increasingly higher proportion of first maternities amongst total maternities and generally lower maternal age. The cause of the increase could not be ascertained because of insufficient information. The decrease in gross frequency which occurred in Italy was found to derive from the smaller number of maternities to women of high parity in recent years. The frequency of twin births to women of corresponding age and parity remained unaltered and differed only slightly from comparable groups of Australian women.

The results of studies on the heredity of the A-B-O groups in a new series of 426 families with 649 children are presented. No exceptions were encountered to the multiple allele theory of heredity of the A-B-O groups and subgroups of A. During the period 1929 to 1952, a total of 1590 families with 3398 children have been tested for the A-B-O groups and only two contradictions to the Bernstein theory of inheritance were encountered, both apparently due to illegitimacy. Statistical analysis reveals a satisfactory agreement between the observed frequencies of blood groups in the children and those predicted under the theory of multiple alleles. While the A-B-O groups are reliable for medicolegal application in cases of disputed parentage, the subgroups of A should not be applied in such cases. The reason for this is that it has been impossible up to now to prepare anti-A1 reagents of satisfactory titer, avidity, and specificity, comparable to anti-A and anti-B reagents which are available. As a result, subgrouping tests, particularly of newborn babies, do not give entirely reliable results.

1. Description of an identical, concordant, deaf mute twin suffering from a perceptive deafness. In the family there occurs no more deafness, on the other hand there are many twins, both M T and D T among their relatives.

2. Description of an identical, concordant, “hearing mute” twin. Up to their eigth year they did not talk at all, they learned speaking when they made their entrance into the Institute for deaf-mutes. They are feebleminded. A brother speaks badly and is slow in intellect too, three cousins of their mother were idiotic.

Data of 986 twins from the records of the Clinica Ostetrica of the University of Rome have been analysed as regards the distributions, means and standard deviations of mother's age, order of birth, birth weight and length of gestation time in groups of like and unlike sex.

The chief characteristic of these data compared with similar data from English hospitals is the inclusion of cases of low birth weight and short gestation time. In the English data there are 9 cases out of 1137 of the group of weight under 680 g; in the present data there are 57 out of 1942 which fall into the lowest group under 500 g.

Similarly in length of gestation the English data have only 2 cases out of 926 under 170 days compared with 33 of the Italian out of 945.

The correlations between twin weights are respectively .8030 for like sex and .7604 for unlike sex; for weight and gestation period they are .3814 (like sex) and .3606 (unlike sex).

The regression of weight on length of gestation runs as a smooth curve in accordance with previous findings. The mean weights for given gestation times are about the same as, or a little higher than, those for the English data.

I am greatly indebted to Dr. Norma McArthur for giving me a copy of these data.

We researched a total number of 3974 persons for the frequency of simian lines and all the material is based on 375 monozygotic, 360 dizygotic, 226 twins of different sex and 2045 single persons of two groups of the population. We classified the material collected into three degrees of impress of the simian line: a little form « 3 », a middle form « 2 » and the classical simian line, called form « 1 ». The form « 3 », which was more frequent to be seen than the form « 1 » and « 2 » seems to contain characteristics of « accidental » genesis without any relation to classical simian lines. That was to be found especially in the case that the little form was only on the surface of one hand. In contrast to that the form on both hands allows the deduction, that there must exist a relation to simian lines. The relations between the forms « 1 » and « 2 » are more evident than these of the little form « 3 ».

The classical simian line seems to be more frequent on the left hand and with the male sex than on the right hand and with the female sex. This picture is a counterpart to the behaviour of thenar patterns.

The result of the average population ist applicable to twins, too. Furthermore it was possible to show by arithmetic, that the concordant reactions of the monozygotics and the discordant reactions of the dizygotics are based on the hereditary character of simian lines and their transitional forms. There is a remarcable difference between monozygotic and dizygotic which is caused by the fact, that discordance of monozygotic is to be found in the case that one partner is one-sided affected with. Moreover the discordant forms become less frequent, if the degree of impress increases. The dizygotics are in the inverse ratio.

The absolute concordance, too, that means the same degree of impress on the same hands of both partners, is more frequently to be found in the case of monozygotic than in the case of dizygotic.

Heberden's nodes or osteoarthritis of the finger joints are described in two identical twins. The appearance of the hands and the bone changes in individual joints as shown by radiographs are remarkably alike. That the twins are identical is indicated by agreement of eye color, hair on the fingers, tasting of phenylthiocarbamide and of 8 blood groups. Evidence of a tendency to mirror imaging in the distribution of the disease among the fingers is seen.

Osteoarthritis of the fingers occurs in these cases in the apparent absence of manifestations of osteoarthritis in other joints. Heberden's nodes is an hereditary disease but this seems to be the first description published of its occurrence in twins.

Report of the result of familial examinations on 49 stillborn of before half year of life died and dissected children with lethal anomalies.

1. In two of 4 families, whose probands suffered from harelip and clett palate combined with other deformities, is supposed, that—just like harelip and clett palate without other malformations—an unstable dominant gen being origin of the mistake of development.

In one case with a special severe combination and probable consanguinity of the parents is to think of homozygoty.

In a fourth case the question of the origin of the combined deformities by « psychical trauma » may be discussed.

2. In 32 families the cause of death of the probands is to be seen in a lethal closing mistake of the vetebral column.

a) In seven of 20 families with an anencephalus signs of « Dysraphies » and other anomalies were found which may be caused by pathological gens. One time both parents of a (homozygote?) anencephalus who showed deformities of heart and limbs had Spina bifida occulta.

b) In 5 of 12 families with Spina bifida aperta was the cause of deformation an unstable unregular dominant gen. In two other families is this probable.

Anencephalie and Spina bifida aperta may be found together in the same family. Heterogenie ist probable for both.

3. a) Hydrocephalie without other deformities was in 8 families not inherited.

b) 4 families with microcephaly showed differences. Dominant gens for « Dysraphies » and recessive gens may bring about microcephaly.

c) Consanguinity of the parents in a case of cyklopy is seen to be sign of recessive inheritance.