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GLOSSARY 



Acquired Character. A feature developed during the life of the 

 individual possessing it, in response to the action of use or 

 environment. 



Albino. An animal without pigment in the skin, hair or eyes. 

 The hair is white ; the eyes pink owing to the colour of the 

 blood. Among plants, white-flowered varieties are called 

 albinos. The condition is called albinism. 



Allelomorph. One of a pair of alternative Mendelian characters. 

 When a pair of characters are alternative in their in- 

 heritance, and segregate from each other in the formation of 

 the germ-cells of an individual which contains both, they are 

 said to be allelomorphic with each other. See Segregation. 



Anther. The part of the stamen in a flower which contains the 

 pollen. 



Chromogen. A colourless substance which when oxidised gives 

 rise to a coloured body (pigment). 



Chromosome. A body in the nucleus of a cell, which absorbs stains 

 and becomes clearly visible during nuclear division, but be- 

 comes dispersed through the nucleus during the resting phase. 

 During nuclear division each chromosome becomes accurately 

 halved, so that in general all cells of each species of animal 

 or plant contain an equal number of chromosomes. 



Continuous. See Variation. 



Determinant. The hypothetical unit in a germ-cell which 

 determines the production of a particular character in the 

 individual derived from that germ-cell. See Factor. 



