v FORMS OF HEREDITY 249 



man as well as in animals, and this form of heredity 

 may be direct as well as crossed. 



6. Re inverted Heredity. The progeny may, at first, 

 and during some time, closely resemble one of the 

 progenitors, and later on, resemble 'the other. 



7. Homotopic Heredity. In this case, a given 

 peculiarity of one of the progenitors is met with in 

 the progeny exactly in the same part of the body as 

 in the former ; for instance, a differently coloured 

 lock of hair, or a naevus maternus similarly placed in 

 progenitors and progeny. This form may be also 

 direct or crossed. 



8. Heterotopic, or Homo/list Heredity. Peculiarities 

 in one part of a progenitor may be transmitted to 

 other parts (made of similar tissue) in the progeny ; 

 the same disease, for instance, may assume one form 

 in progenitors, and another in the descendants. 



The natural sequel to experiments in- crossing will 

 be experiments in hybridisation, that is, crossing 

 between distinct species. New hybrids must be 

 obtained, and the number of those which are fertile 

 inter se must be largely increased. And then, will the 

 latter hybrids form permanent varieties or species ? 

 Experiment only can decide. And while experiment 

 and artificial impregnation may go a long way in 

 creating entirely new and unexpected forms of life, 

 which may be of great interest, particular attention 



