380 SUMMARY 



metimes in the mesoderm. The author explains this by the follo- … 
wing hypothesis; the germinal factor really can act in different — 
tissues. The clinical result is the same whether we have to do with a 
primar ectodermal or mesodermal abnormality, but the genotypic 
difference may manifest itself by a different hereditary behaviour. _ 
As yet nothing is known about other genotypic or paratypic influ- 
ences on the dominant or recessive behaviour or the variability of 
the abovementioned characters nor of couplingphenomena. 
Lx 
