Ectopic pairing in the salivary chromosomes of mosquitoes.

Besides, more common and better known somatic pairing of homologous chromosome regions (Painter 1933), another kind of pairing has been observed which involves bands at non-homologous positions along the chromosome(s) . Bridges (1935) was the pioneer to report this type of pairing in the salivary chro mosomes of Drosophila melanogaster, and later Metz and Lawrence (1938) and Metz (1947) observed it in Sciara. Workers like Prokofyeva-Belgovskaya (1941), Kaufmann (1939, 1944, 1946) and Kaufmann et al. (1947, 1948) referred to this type of pairing as the 'non-homologous conjugation of chromosomes' or 'non homologous associations' in the salivary chromosomes of D. melanogaster . Slizynski (1945), however, replaced the above terms with 'Ectopic pairing'.