492 



3- 



(Orthoptera). 



{b) Interphase, Relic Spirals. 

 Tulip a. Newton, 1927. 

 Gasteria. Taylor, 1931. 

 Lilium. Kato and Iwata, 1935. 

 Tradescantia. Kato, 1935. 

 Fritillaria. D., 1935 a. 

 Podophyllum. D., 1936 ^. 



[c ^) Prophase, Relational Chromosome Spirals. 

 Zea. McClintock, 1933 (presumed). 

 Fritillaria. D., 1935 a and h. 

 Chorthippus. D., 1936 d. 



{c 2) Prophase and Metaphase, Relational Chromatid Spirals. 

 Chorthippus. D., 1936 b. 

 Fritillaria. D., 1936 c. 



Meiosis (2nd Division). 



{a ^) Metaphase and Anaphase, Minor Spirals. 

 Tradescantia. Kuwada and Nakamura, 1935. 

 Lilium. Kato and Iwata, 1935. 



[a ^) Metaphase and Anaphase, Major Spirals. 



Sagittaria (sometimes). Shinke, 1934 '> Kato and Iwata, 1935. 

 Lilium longiflorum. 



(b) Metaphase, Relic Spirals. 

 Fritillaria. D., 1935. 

 Podophyllum. D., 1936 e. 



Permanent Prophase (Salivary Glands). 

 Relational and Relic Spirals, 

 Drosophila, Koller, 1935. 



3. EXTERNAL MECHANICS OF THE CHROMOSOMES 



(i) Attractions, (a) Specific Attractions. In homozygous diploid 

 organisms an association occurs between corresponding chromo- 

 meres of homologous chromosomes in pairs at zygotene. In similar 

 tetraploids a similar association occurs in pairs, but changes of 

 partner take place along the chromosomes, each of which pairs 

 evidently with the nearest of its possible partners at any particular 

 place. This association evidently depends on a primary attraction 



