He worked especially on cytoplasmic inheritance in mosses and fireweed.

In his 1909 paper, he established variegated leaf color as the first conclusive example of cytoplasmic inheritance.

Michaelis, P (1959) Cytoplasmic inheritance and the segregation of plasmagenes.

Cytoplasmic inheritance and intragenomic conflict.

Extranuclear inheritance or cytoplasmic inheritance is the transmission of genes that occur outside the nucleus.

Michaelis, P (1954) Cytoplasmic inheritance in Epilobium and its theoretical significance.

Around 1900, Carl Correns used Mirabilis as a model organism for his studies on cytoplasmic inheritance.

Elected to Fellowship of the Royal Society in 1970 he is best known for his studies of cytoplasmic inheritance and quantitative genetics.

Correns produced the first evidence of cytoplasmic inheritance, in his 1909 paper on variegated leaf colour in Mirabilis jalapa.

He also discovered cytoplasmic inheritance, an important extension of Mendel's theories, which demonstrated the existence of extra-chromosomal factors on phenotype.

Michaelis, P (1966) The proof of cytoplasmic inheritance in Epilobium (a historical survey as an example for the necessary proceeding).

His untimely death at 57 cut short a distinguished career with many contributions in the fields of microbial genetics, cytoplasmic inheritance, and biometrical genetics.

Extranuclear inheritance (also known as cytoplasmic inheritance) is a form of non-Mendelian inheritance first discovered by Carl Correns in 1908.

Michaelis firmly believed in complex unity in the cytoplasm, but he rejected simplistic notions such as the plasma gene or that the cause of cytoplasmic inheritance was solely due to plastids and mitochondria.