404 BREAKDOWN OF GENETIC SYSTEMS 



Table 62 



Classification of Genotypically Conditioned Abnormalities 



of Meiosis 



I. Failure of Metaphase Pairing due to Failure of Chiasm a Formation 

 UNDER Ascertained Conditions. 



Not Associated with Semi-mitotic Contraction. 



Zea Mays (asynaptic) .... 

 Datura Stramonium (bb) 

 Crepis capillaris (" X-strain ") 

 Triticum vulgare * . . . . 



(6) Associated with Semi-mitotic Contraction. 

 Matthiola incana (long-chromosome type) 



Beadle, 1930, 1933 b. 

 Bergner et alii, 1934. 

 Richardson, 1935 c. 

 Hollingshead, 1932. 



Lesley and Frost, 

 Philp and Huskins, 



Shimotomai, 193 1 h. 

 Lamm, 1936. 



Chrysanthemum (small nuclei from pre- 



meiotic irregularity) 

 Secale cereale (inbred) .... 

 Ascaris megalocephala bivalens (one 



individual) Geinitz, 191 5. 



(c) Associated with Timing Irregularities. 

 Ochna serrulata (facultative parthenogenctic 



embryo-sac mother-cell) 



Eu-Hieracium spp. (parthenogenctic) 



Nicotiana Tabacum (variety with un- 

 reduced gametes) .... 



Aticuba japonica * .... 



Primus hybrids * . . . . 



Triticum vulgare * . . . • 



Drosophila pseudo-obscura, inter-race 

 hybrids ...... 



(d) Under Undefined Cytological Conditions. 

 Nicotiana alata {2X +1) 

 Nicotiana Tabacum {" Pale sterile "), 



1927 

 1931- 



Chiarugi and Francini, 1930. 

 Rosenberg, 1927. 



Rybin, 1927. 

 Meurman, 1929 a. 

 D., 1930 a. 

 Hollingshead, 1932. 



Dobzhansky, 1934. 



Avery, 1929. 



R. E. Clausen, 1930, 1931. 



^x + 1 . 

 Triticum vulgare X 



line derivative 

 Triticum vulgare {6x — 

 Avena sativa (6x — 2s^ 



T. durum, 6x pure 



-2) : : : 



Sorghum sp. ..... 



Primula kewensis {4X — 2) . 



Primula malacoides .... 



Hevea sp. ...... 



Viola Orphanidis (male sterile) 



Rumex Acetosa ^ .... 



Angiostomum, Rhabditis and other 



Nematoda {X chromosomes in special 



circumstances, Ch. IX). 

 PygcBra pigra X P. curtula S (nearly 



complete pairing in female) 



L. A. Sapehin, 1931. 

 Huskins and Hearne, 1933. 

 Huskins, 1927 ; Nishiyama, 



1931. 1933. 1935- 

 Huskins and Smith, 1932. 

 Newton and Pellew, 1920. 

 Kattermann, 1934. 

 Ramaer, 1935. 

 J. Clausen, 1930. 

 Yamamoto, 1934. 



Federley, 1931. 



* Irregularities in particular cells with reduced pairing or restitution 

 nuclei resulting from reduced pairing. 



