APPENDIX I 



Polymorphism {contimted) 

 Cryptic Polymorphism, such as is not distinguishable by external 

 morphology. 



Polyploid, an individual having three (Triploid), four (Tetraploid), 

 five (Pentaploid), six (Hexaploid) or more complete sets of 

 chromosomes instead of two as in the Diploid {v. AUo-, Auto- 

 polyploid). Winkler 1916. 

 Di-, Tri-, Poly-Basic Polyploid, Allopolyploid derived by the 

 addition of diploid complements with two, three or more basic 

 numbers. Darlington and Janaki Animal 1945. 

 Secondary Polyploid, a homozygous allopolyploid in which some 

 of the types of chromosomes in the basic set are represented more 

 frequently than others. Darlington and Moffett 1930. 

 Unbalanced Polyploid, v. Aneuploid. 



Polysomic, an otherwise diploid individual having one chromosome 

 represented three (Trisomic) or four (Tetrasomic or doubly 

 Trisomic) times instead of twice {2x -\- i, 2x+ 2). Blakeslee 1921. 

 Polysomic Inheritance, that which arises where any chromosome in 

 a polyploid or polysomic individual has more than one possible 

 partoer at meiosis. By analogy Tetrasomic Inheritance, Hexasomic 

 Inheritance, etc. Blakeslee, Belling and Farnham 1923. 



Polyspermy, the entrance into the egg of more than one sperm, under 

 normal and abnormal conditions, whether effective or ineffective 

 in fertihzation. 



PoLYTENE Nucleus, one in which protein production and gene 

 reproduction go on side by side. A permanent stage in which the 

 chromosomes are represented by many linearly stretched and paired 

 threads in the Diptera, especially in the sahvary glands. Koller 



1935. 



Population, i. (genetical), a Mating Group hmited for special con- 

 sideration either by environment 01 breeding system. 

 2. (statistical), the hypothetical infinitely large series of potential ob- 

 servations or individuals, of which those observations or individuals 

 actually obtained form a sample. 



Position Effect, the difference in effect of two or more genes according 

 to their spatial relations in the chromosomes. An effect of intergenic 

 structural change, v. Gene, Mutation. Sturtevant 1926. 



Post-Reduction, as opposed to Pre-Reduction. Korschelt and Heider 

 1903. 

 I. The alleged reduction of the number of chromosomes at the 

 second, as opposed to the first, meiotic division (obsolete). 



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