158 GLOSSARY 



members of an allelomorphic pair of characters, the member 

 of the pair which does not appear in the offspring is called 

 recessive. 



Reversion. A ' throw-back ' to a previous ancestor, or to the 

 type of the species, when varieties are crossed. 



Segregation. In Mendelian inheritance, the separation of the 

 two characters of an allelomorphic pair, in a heterozygote, 

 into distinct germ-cells, i.e. the formation of gametes each 

 bearing one character of a pair, by an individual which 

 contains both members. 



Self -fertilisation. The fertilisation of a female gamete by a male 

 gamete produced from the same individual The process in 

 plants is spoken of shortly as selfing. 



Somatic. Having reference to the body {'soma') considered as 

 distinct from the germ-cells. A character borne or exhibited 

 by the body but not represented in the germ-cells is called 

 somatic as contrasted with germ.inal. 



Spermatozoon. See Germ-Cell. 



Style. The part of a flower which receives the pollen, and con- 

 ducts the male germ-cell to the egg-cell. 



Telegony. The supposed influence of a former sire upon young 

 born to a later sire by the same mother. 



Type. The normal form of a species, which is regarded as 

 typical. 



Variation, Variability. The differing among themselves of 

 individuals of the same species. When the extreme forms 

 are connected by a complete series of intermediates, the 

 variation is Continuous; when distinct forms occur, not 

 connected by intermediates, it is Discontinuous. 



Zygote. An individual produced by the union of two gametes. 



