LIST OF TABLES 



PAGE 



Chapter I 



Table i. Variation in the Haploid and Diploid Generations . . 6 



Chapter II 



Table 2. The Time Taken by Division of the Nucleus . . -31 



3. Estimated Total Lengths of Chromosomes in Complement 



(in microns) ........ 31 



4. Relatives Sizes of " Solid " and 'Vesicular " Nuclei . . 46 



Chapter III 



Table 5. Lengths of Chromosomes in Species and their Hybrids . 56 



,, 6. Types of Chromosome Constitution ..... 61 



,, 7. Instances of Syndiploidy in Male Germinal Cells . . 65 



8. Analysis of Variation in Crepis ..... 70 



9. Organisms with an Extreme Range of Size in the Chromo- 



somes . . . . • . . . .81 



10. Range of Size and Number of Chromosomes in Animals and 



Plants 83 



Chapter IV 



Table 11. Examples of a Diffuse Stage at Diplotene or Diakinesis . 94 

 ,, 12. Classification of Organisms according to the Distribution of 



Chiasmata in their Longest Chromosomes at Metaphase 1 1 o-i 1 1 

 ,, 13. Lagging of Bivalents with Interstitial Chiasmata . . 115 



14. Observation of Meiosis in Auto-Polyploids . . . 125 



15. Variation in Pairing of Chromosomes in Triploids and 



Tetraploids 126 



Chapter V 



Examples of Supernumerary Fragment Chromosomes 

 Chiasma Frequencies of Fragments .... 

 Pairing in Tetraploid Interchange Heterozygotes 

 Classification of Interchange Heterozygotes 

 Classification of Unequal Bivalents .... 

 Classified Observations of Pairing of Chromosomes in 

 Undefined Hybrids ...... 



22. The Fluctuation of Chromosome Pairing in Hybrids . 



23. Chiasma Frequency of Hybrids Compared with that of 

 their Parents ....... 



24. Observations of Salivary Glands in Diptera 



145 



146 



159 

 159 



161 



172 



174 



175 

 178 



