320 ILLINOIS STATE ACADEMY OF SCIENCE 



suggested, however, that the difference in the severity of 

 the disease is due to different modes of infection. It is 

 thought that this is more probable than that there is a 

 difference of immunity in the two fetuses. 



Mortality. Twins in general are characterized by low 

 vitality. The death rate is much greater than in single 

 newborns. In the first weeks the mortality is forty 

 percent. It is generally stated that twins have thirteen 

 times less chance to live than ordinary newborn babies. 

 In the report of Miller's cases at the Moscow Infant 

 Asylum, 3883 pairs of twins were observed among 277,- 

 902 children. 62.9 percent of these died during the first 

 weeks of life. In half of the cases, both twins died on 

 the same day. In the remainder, the one lived one or 

 two days longer. Septicemia and syphilis were frequent 

 causes of death. The greatest mortality of those infants 

 who survived the first few weeks of life seems to con- 

 centrate in the first and second year. After the fifth 

 year of life, the mortality of twins and non-twins is about 

 the same. 



It has been estimated that out of a hundred pairs of 

 twins born there are eighty pairs who survive. In fif- 

 teen pairs, only one child survives; in five pairs both 

 children die. According to Hecker, fifteen percent die 

 during the first eight days. It has also been said that 

 twin girls seem to have greater viability than' twin boys. 



Since Galton's memorable studies no investigation has 

 been conducted on the pathological aspect of twins. The 

 British Medical Journal of 1912 contained a very in- 

 teresting and suggestive editorial on twinship and fame. 

 The editorial was suggested by the remarks of Doctor 

 Kaiser, of Dresden, who stated that he knew of no 

 famous man who had a twin brother. A similar query 

 had been raised by Doctor Simpson in the Edinburgh 

 Medical Journal of 1862. Simpson was not aware of a 

 single instance in which a twin had distinguished him- 

 self intellectually. The editorial writes takes issue with 

 these gentlemen, and goes on to show that there were 

 several twin brothers who had won more or less fame. 

 In attempting to collect information on this subject, it 



