0 Lakshminarayana, K. V. 1979 Bulletin of the Zoological Survey of India 2 1 29-34 37700 It has been recognised that asymmetry palys a considerable part in animal speciation., particularly in insects. This aspect has been examined in certain "chewing-lice" infesting birds. Two kinds of asymmetry is noticed., one affecting the body parts other than genitalia, and the other only genitalia. While the former is due to the ecological adaptions, the latter occurs during the sympatric speciation. Occasionally asymmetric forms also appear due to accidental damage, as in certain individuals hurt during preening , but recovered from the injury. pdfJournal http://www.phthiraptera.org/Publications/1131.pdf