APPENDIX I 



Sport, a dissimilar form of an individual, or part of an individual, 

 arising directly or indirectly from gene, plastid, chromosome or 

 nuclear (polyploid) Mutation. The indirect origins arc due to 

 Segregation of a recessive gene, cellular sorting-out of Plastids, and 

 tissue sorting-out in Chimacras. The name is usually confmed to 

 new and unforeseen forms. 



Square, Latin Square, an experimental design involving tv^o restraints. 

 Mean Square, average of the squared deviation of observations from 

 their mean. Found as the ratio of the Sum of Squares to the Number 

 of Degrees of Freedom. Synonymous with Estimated Variance. 

 Method of Least Squares, a method of estimation depending on 

 minimization of sums of squares, and widely used in Regression 

 analyses. 

 Sum of Squares, the sum of squared deviations of observations from 

 their mean. 



Standard Deviation, v. Deviation. 



Standard Error, v. Deviation. 



Statistic, the estimate of a Parameter arrived at from an observed 

 sample. Bears the same relation to the sample as the parameter 

 does to the population, v. Likelihood. 

 Consistent Statistic, one which tends to approach the parameter in 



value as the sample size increases. 

 Efficient Statistic, one which tends, as the sample size increases, to 



use all of the information available in the data. 

 Inefhcient Statistic, one which uses less of the information than an 



Efficient Statistic. 

 Sufhcient Statistic, one which uses all the information available in 

 the data, even as small samples. Not always available. 



Stem Body (Stemm-Korper), the part of a spindle between two groups 

 of chromosomes separating at anaphase. Belar 1928. 



Step Allelomorphism, the occurrence of a series of Multiple Allelo- 

 morphs with overlapping effects, which can supposedly be related 

 to a linear order in the distribution of units of change within die 

 gene. Deduced from the scute gene in Drosophila melanogaster. 

 Scrchrovsky 1930. 



Sterility, any failure (partial or complete) of an individual under given 

 environmental conditions to produce effective gametic or viable 

 zygotic progeny. May be due to environmental or gcnotypic defects 

 or to segregation in a hybrid or polyploid. Genotypic defects in the 

 gametes are due to segregation in a hybrid parent, and in zygotes 

 to unbalance in die hybrid individual concerned. 



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